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I’ve been using a Mettler-Toledo (MT) RC1e reaction calorimeter for about 6 years. Our system came with MT’s iControl software, RTCal, and 2 feed pumps with balances. Overall it has proven its worth for chemical process safety and has helped us understand and adjust the thermal profile of diverse reactions. Like everything else, MT’s RC1e has many strengths and a few weaknesses.

The RC1e’s mechanical side seems reasonably robust. Our instrument sits in a walk-in fume hood resting on a low lab benchtop supported by an excess of cinder blocks- it is a heavy beast. During installation we discovered that the unit would not achieve stable calibration with the hood sash down. The control box mounted on the instrument didn’t work properly on installation. After a trip to the repair shop, the box was returned as functional but without finding the fault.

Recently we had a mixing valve fail in the heat transfer plumbing, resulting in down time. Diagnosis of this was unsuccessful over the email and phone, necessitating a service call. Parts may not be inventoried in the US and consequently must come from Switzerland. Expect Swiss prices and less than snappy delivery. Hey, it’s been my experience.

A chiller unit is required for RC1 operation and can add 15-30k$ to the setup cost. Users will have to contend with the loss of floor space in the lab for the chiller and RC1. Chillers can take many hours to get down to the set temperature. Given that RC1 experiments can also be lengthy, plan accordingly. Our (brand new Neslab 80) chiller requires nearly 2 and 1/2 hours to get from +20 C to -20 C, which is the upper chiller temperature we use, depending on the reaction chemistry. For reactions that are on the sporty side, we’ll drop the chiller to – 50 C.  This is near the  minimum temperature for the water-based chilling fluid we use. Early on I opted for an aqueous lithium formate solution with a very low freezing point. It’s a little spendy, but a pool of it on the floor cannot warm up to become combustible and an ESD ignition hazard. Also, it is odorless.

The chiller required the wiring-in of a dedicated single-phase 240 VAC circuit. With the chiller using single-phase and the RC1e using 3-phase 240 VAC, it is important to assure that one cannot inadvertently connect into the wrong power circuit (idiot proofing). The chiller plug design should already prevent this. It is critical that the electrician is alert to this and does NOT jury-rig the plugs to use the same style of connectors because he has only one style in the parts bin.

Some comments on the collection and interpretation of RC1 thermograms.

  • It is critical that those who request RC1 experiments understand the limitations of the instrument. For instance, we use a 2 Liter reaction vessel with a 400 mL minimum fill volume. Refluxing is not allowed owing to the huge thermal noise input from the reflux return stream. Special equipment is said to be available for reflux.
  • Experiments must be carefully designed to elicit results that can answer questions about feed rates and energy accumulation.
  • Like many instruments, the RC1 needs a dedicated keeper and contact person for inside and outside communication. A maintenance logbook should be kept next to the instrument if for no other reason than to pass along learnings from previous issues.
  • If thermokinetic measurement is part of your organization’s development SOP, someone on staff should be reasonably familiar with chemical thermodynamics. That can be a chemical engineer, as may often be the case.
  • The users of thermal data are likely to need help with interpretation of the results. Be prepared to offer advice on interpreting the data, taking care not to over-interpret. If you don’t know, say so. It is easier to claw back “I don’t know” than “yeah, go ahead and do that …”.
  • Do not be anxious to singlehandedly bear the weight of responsibility for safety. Safety is a group responsibility.
  • Be curious. How do the insights and learnings from the data translate into best practices? What changes, if any, can the process chemists make to nudge the process for better safety and yields? A credible specialist in RC can make comments or ask questions that lead to better discussions on thermal hazards. Be a fly in the ointment.
  • Never forget that a reaction calorimeter is a blunt instrument for the understanding of a reaction. An RC1 thermogram is a composite of overlapping solution-phase phenomena. Interpretation of results can be greatly refined by pulling timely aliquots for NMR, GC/MS, or HPLC analysis.
  • A database should be constructed to collect and immortalize learnings from all safety work and RC1 learnings fall into that group.

There is the question of who collects and presents the data. An engineer or a chemist? Engineering thermodynamics is a big part of a chemical engineer’s education and skill set. As a plus, an engineer can take thermal data and apply it to scale-up design for safety and sizing of equipment and utilities. You know, the engineering part.

Do not be anxious to singlehandedly bear the weight of responsibility for safety. Alpha males- are you listening??  Safety is a group responsibility that should originate from a healthy group dynamic.

There’s a good argument for a chemist to conduct RC experiments as well. A trained synthesis chemist is qualified to conduct chemical reactions within their organization. That includes sourcing raw materials, handling them, running the reaction, and safely cleaning up the equipment afterwards. But interpreting RC1 data has a large physical chemistry component. In my experience, run of the mill inorganic/organic synthesis people may have seen PChem as an obstacle rather than a focus in their college education. Their skill set is in instrumental analysis like NMR and chromatography, mechanisms, and reaction chemistry. I would recommend having a PhD chemist with a focus on thermo in a leadership role when calorimetry is a key part of a busy process safety environment.

Safety data can be collected and archived all day long. The crucial and often tricky part is how to develop best practices from the data. I would offer that this is inherently a cross-disciplinary problem. Calorimetric data from reaction chemistry can be collected readily, especially with the diverse and excellent instrumentation available today. Adiabatic temperature rise, ΔTad, can be determined by a chemist, but it’s the engineers who understand how the equipment may respond to a given heat release. A smooth and efficient technology transfer from lab to plant happens when good communication skills are used. Yes, SOP’s must be in place for consistency and safety. But the positive effect of individuals who have good social skills and are prone to volunteering information cannot be underestimated.

 

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An automated Windows update disrupted my life today. It swooped in overnight like a winged wraith, did its dark deeds, and flapped quietly back to the dank hole from whence it came. My RC1 data may yet reside unscrambled on the disk drive, but it lies orphaned from the mother iControl application which mockingly professes no recollection of 18 hours of sweet data lovingly produced. The curs in IT can only “tsk, tsk” in their antiseptic way while bobbing pointed heads in faux dismay. Another first-world difficulty uncovered for all to see.

The electronic news world is a colossal hodgepodge of media jumping on anything new and “compelling”. The weekend’s compelling news du jour is Ret. Adm. Mike Mullen‘s comments on the likelihood of nuclear war with North Korea (DPRK). As a retired admiral and chairman of the Joint Chiefs, Mullen is a strategic thinker. These days he is very pessimistic of the US finding a peaceful way forward with the DPRK.

Taken alone, this view could be ignored as an outlier. But against a backdrop of other seemingly credible reports, Mullen’s worry could be taken as another indicator of the tempo of concern within much of DC. Consistent with Mullen’s worry is a lengthy 12/14/17 interview with Senator Lindsey Graham written by Uri Friedman at The Atlantic. Graham is an opinion leader on the matter of the DPRK. The article is well written and I must highly recommend it.

The frothy part of this DPRK boil-up is talk of nuclear conflict. The language that I have heard does not distinguish the various scenarios of how a nuclear war would unfold on the Korean Peninsula. One thing that was made clear by Graham in the Atlantic article is that there could be no limited strike on the DPRK. I assume it means defensively or otherwise. Any attack on the North, nuclear or conventional, would have to result in the complete collapse of the Kim regime.

The US military develops and refines war plans in preparation for any contingency. But, I’m curious how the psychological impact of the use of nuclear weapons will play in the various war cabinets of the world. After all, the nuclear-bomb genie has been kept in the bottle since August, 1945. Will a first use on or by the DPRK lower the threshold for other nuclear states?

A nuclear weapon married to a missile is a highly engineered machine that is at the apex of multiple military technologies. Expertise and a minimum of infrastructure in metallurgy, nuclear physics, chemistry, propellants, and delivery vehicle technology is necessary for accurate execution of a strike. For the DPRK to maximize the punch of its limited nuclear armaments, a strike relying on accurate delivery of a nuclear war shot to a remote or hardened target would require their leadership to gamble on layers of unproven or unrefined technology. The Kim regime may be a political malignancy, but they are not stupid.

Suppose the DPRK is able to strike some important targets with its nukes. Surely some in the North’s command know the consequences to follow. Decapitation of its leadership and annihilation of its war making capacity are a certainty.

For the US, the use of a nuclear war shot on the DPRK is not an inevitable result of physics like the apple that fell on Newton’s head. A release from the US nuclear arsenal is a choice and thus psychological in both application and long term consequence. Would a US nuclear response to a nuclear strike- anywhere-  by the DPRK make sense for the US in the subsequent post-war world?

The last big war, WWII, started conventional and ended nuclear.  Since then, the threat of mutual nuclear conflagration has helped to keep the peace by serving as a deterrence. Mutual Assured Destruction, MAD, is credited, superficially a least, with keeping armed conflict a strictly chemical explosives activity. What happens to the ground under the psychological pedestal supporting MAD when a nation-state uses nuclear weapons thinking it could win a conflict? How would the various national policies on first use change across the world and what do the likely outcomes look like?

There are many issues that follow from conflict with the DPRK. I hope that as much energy is given to the diplomatic scene as the theatre of war.

12/20/17. It has been perhaps 6 weeks since CAS has fixed the snag with downloading ACS publications directly from SciFinder. This was a problem because, prior to the SNAFU, the ACS downloads directly from within the SciFinder account would be billed in our monthly statement. Without this feature, every download from the ACS Publications siute, outside the SciFinder account, would then be a separate line item on our in-house expense report with the required circulation for signatures, and absent the contractual discount. So, without the download/billing feature, it was a bigger paper storm and higher document pricing.

Whatever the problem at CAS was, it took some time to fix. Hopefully careers are back on track and all is well.

10/20/17. We have upgraded to Chemical Abstracts Service’s new SciFinder-n which includes PatentPak. After 2 weeks of fairly heavy use I find myself not completely convinced of the marginal value of this upgraded version. Some comments that come to mind-

  • The upgrade resulted in loss of the ability to download ACS publications directly from CAS. This is a glitch that the good folks at CAS are said to be working on. I have no idea as to the extent of this problem across the user base. Obviously ACS publication documents are downloadable from the publication website. The other possibility comes from the official document service of the ACS, FIZ Autodoc. FIZ can provide ACS documents, but for a sizeable premium above an ACS document download fee straight from CAS.
  • All upgrades, good or not good, require the user to adapt to new features. For some navigation, SciFinder-n seems to require fewer clicks and windows to begin a search. The application opens with a Google-like query box allowing the user to input a CASRN, text string, author names, etc., without clicking to a specific search entry window.
  • I use every visit by our CAS rep to lay out what I perceive as weaknesses of SciFinder. So far, no sign that my input even made it into the rental car as they sped away. One big annoyance has been the absence of Boolean searching.  If it can do Boolean searching, I have not found the right syntax or link to use it. This would be welcome.  If I’m wrong here, please leave a comment.
  • I’ve noticed that when looking at a list of references related to a substance query the ‘hits’ are no longer given listing numbers. When you find an abstract to look at more closely and then click back to the list of abstracts, you do not return to the part of the page you clicked away from. I can live with that, but since the document abstracts (see below) are not in a numbered list (1, 2, 3, … n)  you must scroll back and find where you left off by recognition of the text. So unnecessary.

10/24/17. I spoke with a customer service rep at Chemical Abstracts Service (CAS) today. It seems that CAS is in the throes of a software fiasco. The feature that allows a CAS customer to download a pdf document from an ACS publication is presently offline system-wide. This feature allows an account holder to download a document and have the charge added to the monthly billing statement. This greatly simplifies the transaction.

The rep, who was very apologetic, said that as of today it looked like the problem would be fixed in 2 weeks for those using SciFinder Web. No such luck for SciFinder-n however. Evidently the “n” version was released before the ACS document download package was available for it (!!). Luckily a SciFinder-n user can open up the web version. Funny thing is, I have no recollection that our regional representative divulged any of such details during his sales call. Simple sod that I am, my understanding was that “n” was an upgrade encompassing all of the previous web version features. Not quite, it appears. The rep said that the ACS download feature on “n” wouldn’t be available until next year.

Using both the web and the “n” versions side-by-side I must confess that I prefer the web version in many ways. Perhaps due to familiarity. I wonder what others think.

 

 

How to follow directions-

  1. Look at the person
  2. Say ‘OK’
  3. Do it

How to do anything-

  1. Start at the beginning
  2. Proceed through the middle
  3. Stop when finished

How to save electrical energy-

  1. When leaving an area, Turn Off the Goddamned Lights!

I’ll confess that I am especially peevish about the last instruction.

What instructions do you have to share, dear reader?

 

Recital.

Whereas contemplation of the lawful removal of the 45th President of the United States is a serious matter; and,

Whereas the President of the United States, Donald Trump, has displayed public behavior that can reasonably be characterized as profane, untruthful, misogynistic, and a demonstrated top-level fomenter of many of the base instincts of man; and,

Whereas the President has consistently displayed conduct, both internationally and within US borders, that is unbecoming of the top-level executive and de facto moral representative of the citizens of the United States of America; and,

Whereas the President has with malice and purpose attempted to incite foreign states with disrespect, schoolyard taunts, slander, and in the case of the DPRK, public threats of total annihilation, nuclear or otherwise; and,

Whereas the President has unilateral control over the release of nuclear war shots while, in this capacity, cultivated a mode of operation that is antithetical to US norms and traditions, and is unburdened by knowledge of the hard earned historical precedents relating to our nuclear weapons complex and decades of successful strategy pertaining to nuclear conflict and their enduring effects;

Therefore, be it resolved that the 45th President of the United States should be lawfully removed the from office by the US Congress under the terms of Section 4 of the 25th Amendment to the Constitution of the United States.

Note: This is only one of a great many possible declarations calling for the removal of President Trump. Focus your thoughts. Try writing and publishing your own.

 

Twenty-fifth Amendment to the United States Constitution

Section 1. In case of the removal of the President from office or of his death or resignation, the Vice President shall become President.

Section 2. Whenever there is a vacancy in the office of the Vice President, the President shall nominate a Vice President who shall take office upon confirmation by a majority vote of both Houses of Congress.

Section 3. Whenever the President transmits to the President pro tempore of the Senate and the Speaker of the House of Representatives his written declaration that he is unable to discharge the powers and duties of his office, and until he transmits to them a written declaration to the contrary, such powers and duties shall be discharged by the Vice President as Acting President.

Section 4. Whenever the Vice President and a majority of either the principal officers of the executive departments or of such other body as Congress may by law provide, transmit to the President pro tempore of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office, the Vice President shall immediately assume the powers and duties of the office as Acting President.

Thereafter, when the President transmits to the President pro tempore of the Senate and the Speaker of the House of Representatives his written declaration that no inability exists, he shall resume the powers and duties of his office unless the Vice President and a majority of either the principal officers of the executive department or of such other body as Congress may by law provide, transmit within four days to the President pro tempore of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office. Thereupon Congress shall decide the issue, assembling within forty-eight hours for that purpose if not in session. If the Congress, within twenty-one days after receipt of the latter written declaration, or, if Congress is not in session, within twenty-one days after Congress is required to assemble, determines by two-thirds vote of both Houses that the President is unable to discharge the powers and duties of his office, the Vice President shall continue to discharge the same as Acting President; otherwise, the President shall resume the powers and duties of his office.  Source: Wikipedia.

The weighty voices of the GOP evangelical propaganda wing have activated following the awful soaking that Houston received. The wagging fingers of TV evangelists were not far behind to remind us of the looming existential threat.

We’ve witnessed a burlesque of  righteous-sounding preachers leaning in from the video pulpit and warning, solemnly and in no uncertain terms, that hurricane Harvey is only the latest in a series of calamities to befall our nation. Our corrupt society is wallowing in a fetid pit of sin and depravity. The storms were heaven sent they intone, to show Who is actually in charge.

It’s all so very clear to these folks. The root cause of the mass murder at Sandy Hook and hurricanes Katrina, and now Harvey is the grievous sin of omission. For what? For failing to put an end to abortion and gay marriage. They’ve been connecting the dots and these dots lead to perdition. An existential threat is on the move. It’s Old Nick up to no good.

The conservative fear machine has kicked into full ruckus configuration. They deploy their weapons of incitement via their heavy presence on AM radio and cable TV. For elections and in the face of national debate, these evangelical conservatives know that they can dependably frighten just enough people to swerve the Republican hive mind. Who are these pliable voters? I think more than a few of them are people who for one reason or another did not take advantage of the education opportunities decades ago and now find themselves near the terminus of a life of toil.

Conveniently for those right of center, the Democratic Party is comatose and strapped into an iron lung, wheezing away the years in an undisclosed location.

9/10/17, Addendum.  In case I was not clear, it’s my observation that conservative protestant evangelical organizations have become a menace to American civilization. It seems to me that the election of Trump and the support bestowed upon him by conservative Christian groups, many of whom can be found out in the open on his evangelical advisory board, has opened the door to opaque theocratic influence on the large scale conduct of American government.

It’s axiomatic that people have an inherent right to worship as they please. So imagine the nightmare of trying to control what people believe when religion is folded into the curriculum of the public schools. What a tragic misunderstanding of human nature it would be to attempt to impose religious doctrine upon students. Parents would have none of it. But, a private school may have much more flexibility to teach a particular sect of religious belief. Is it  a coincidence that privatizing schools is favored by many religious organizations?

Finally, there is the matter of magisteria. Steven J. Gould wrote about religion and science as being non-overlapping magisteria. A magisterium is defined as a “a domain where one form of teaching holds the appropriate tools for meaningful discourse and resolution”. A magisterium may or may not recognize an external system of laws, facts, or values. Gould maintained that science and religion were non-overlapping magisteria in the sense that the tools of science were of no use in solving religious questions.

The secular world can be thought of that which describes what is human made and of human concern. It can also be thought of as that which is independent of religion. It is not atheistic or better or worse in any way. In chemistry we might say that the secular is orthogonal or perpendicular the religious. A bolt, an integrated circuit, or a tractor would be in the domain of the secular. So would the National Electrical Code, city ordinances, and state and federal law. All of these items are contrivances made by people for purposes living a better or safer life. Added to these items would be mathematics, the sciences and engineering. That which is measureable like the Volt or the kilogram have no defining attribute which traces back to religious definition.

It has been said that the purpose of government is to protect ourselves from each other. I would extend that to include the general domain of the secular. Having secular government means that subjective interpretations of religious matters must be secondary. This is owing to the reality that there are many religious beliefs in the world and the question of whose religion will prevail in an action involving the public will rapidly become intractable due to disparate beliefs. The secular world has elements of logic, measurement and guidelines for evidence or objective observation. All of these examples could be contained within a secular magisterium.

Public schools have long been the institutions where secular matters were introduced and learned. Government at all levels has been steadfastly kept within the secular domain. There was and remains to be a need for government to manage the secular details of a thriving civilization. The religious magisterium has a heavy reliance on beliefs which is a subjective matter subject to interpretation. A democracy requires a goodly amount of objectivity and evidence.

The notion of non-overlapping magisteria raises an interesting question. What if elements in one magisterium want control of elements in another magisterium? To have elements of a subjective domain in control of elements in the objective domain is to introduce chaos in both. Since neither side has the tools to operate in the other we have to conclude that this circumstance makes no sense for either domains.

 

I found myself up north in Casper, Wyoming, with friends for the 8/21/17 solar eclipse. We were modestly equipped for the spectacle. A member of our small group brought a Celestron 8″ Cassegrain telescope with solar filter and clock drive. We set up in an uncrowded neighborhood and began the wait.

Knowing that Casper would be crowded I had arrived 2 days early to explore some of the local geology. Jeez- I guess that makes me a geotourist. This activity gives a person a mission to complete. Pick some locations to visit and go do it within your time constraints. There is a beginning, a middle, and an end. Success consists of finding the location of interest, getting samples and photographs of unique rocks, stata and general landforms.

I’ve had good luck with the Roadside Geology series of books by Mountain Press Publishing. In the case of the eclipse trip, I secured a copy of the Roadside Geology of Wyoming ahead of time at a local Barnes and Noble. These books are quite well written and illustrated, especially important if you’re not packing a degree in geology.

The unique value of the Roadside Geology books is that the content is divided into state regions then subdivided into stretches of highway that you can drive along. Commonly along the highway can be seen many large scale features described in the book. Even better, photographs and diagrams of road cuts are frequently highlighted. In hilly or mountainous regions there are many road cuts that allow you to view underground features.

Lately I’ve taken to wearing a yellow reflective vest along the roadside while taking a close look at the exposed formation. People don’t expect to see some yay-hoo walking along the road with a  hammer and a notebook as they careen around the curves on a mountain road. Best not to surprise drivers.

Teapot Rock north of Casper, Wyoming.

There is a bit of interesting US history attached to the geology of the Casper area. The Teapot Dome scandal erupted during President Warren G. Harding’s administration in 1922. Harding’s Secretary of the Interior, Albert Bacon Fall, was caught taking bribes in exchange for awarding oil rights to a subsidiary of the Sinclair Oil Company.  The oil field was within the Navy Petroleum Reserve north of Casper.

“Teapot” Dome takes its name from Teapot Rock– a formation that, at the time, had a feature that resembled a spout. This feature is no longer there. “Dome” comes from an anticline fold in the oil bearing stata below. It is part of the larger Salt Creek Oil Field.

The seeing in Casper was good right up to the back third of the eclipse. The Celestron was rigged to throw an image onto a white screen. A chain of sunspots were visible early in the eclipse. As I was equipped with only my Samsung 6 for photography, I did not manage to get great pictures, nor was it really my intent. Sometimes you have to put the camera down and look. Just before totality we saw Baily’s Beads and the diamond ring. The autofocus of the Samsung was unable to produce a sharp image of the beads on the projection owing to the low light level.

Close-up of sunspots early in the eclipse.

When totality arrives you can look at it directly with the naked eye. It’s best to view it without the distraction of equipment. During totality it became noticeably cooler. The eclipsed sun had a wispy corona around it, reaching into space. Around the horizon back on the ground was a beautiful 360 degree sunset. People in the neighborhood were cheering. What a thing to see.

 

Pinhole projection using aluminum foil and a cereal box.

 

Here you can see some knucklehead trying to get a view through a pinhole projector cleverly disguised as a box of corn flakes. He commented that the image was only slightly better than nothing. In fact the image projecting through a colander onto the pavement was superior (below).

 

 

 

 

 

Multiple images of eclipse as projected through a colander.

 

Dear Samsung,

I have owned a Samsung S6 smartphone for several years. Permit me to offer an appraisal of this device.

Satisfactory Attributes

  1. Satisfactory reliability
  2. Appearance, size, and weight.
  3. Fits in most shirt pockets for maximum personal utility.
  4. Several useful functions and features.
  5. A QWERTY keyboard for faster texting.
  6. Takes video and stills.
  7. Sends video and jpeg files.

Unsatisfactory Attributes

  1. Bad, bad ergonomics overall.
  2. Silicone protective cases prevent easy insertion into shirt pockets.
  3. No inactive margin on screen side by which to hold the phone without activating some feature.
  4. In general the worst ergonomics possible for a camera. It would be difficult to worsen the design.
  5. Subject to mandatory creeping featurism. This is a type of cancer.
  6. Screen difficult or impossible to see in outdoor daylight.
  7. Too many features. In this regard it resembles a universal kitchen tool. Eventually you realize that all you really wanted was to dice the potatoes.
  8. I frequently lose photographic opportunities because the f*cking camera was inadvertently toggled into some other mode, preventing activation of the “shutter”. See #3, this section. !%#@*&@#*&!

What do I really want?

  1. A flip phone that has a QWERTY keyboard, or
  2. A good purpose-built camera that offers basic telephony.

Why do I continue to use it?

  1. Expectation of accessibility by family, friends, and employer.
  2. Connection with friends and distant family via facebook.

Summation

Samsung, I pity you because you are stuck on the endless treadmill of ever increasing novelty. Because of this users are forced to adapt to updates of the Système du jour. I only wish that S6 purchase transactions would change in like manner. Listening to Samsung bitch about having to alter their enterprise system annually to accommodate the hidden needs of unknown organizations would bring a bit of cheer in a sadistic kind of way.

 

Enroute to other things I ran across an old Gulf R&D patent, US 3294685, titled “Organic compositions containing a metallo cyclopentadienyl”. Sifting through the description my eye caught the interesting content below:

July 1941. A test spray was prepared by dissolving 2.5 grams (3.2 percent) of iron dicyclopentadienyl in ml. of a typical household insecticide base oil. The tests made with this solution employed a dosage of IO-second discharge. An equilibrium :period of 15 seconds followed by an exposure period of 70 seconds, during which the mist was permitted to settle on adult house flies confined in a screen-covered dish, was employed in the tests. The results of the tests showed that of the flies which had been contacted with the base oil containing 3.2 percent by weight of iron dicyclopentadienyl, 53.6 percent were dead after 24 hours. Of theflies which were contacted with the base oil alone, only 13.0 percent were dead after 24 hours. Check flies which were confined for 24 hours without having been contacted with either the base oil or the base oil containing iron dicyclopentadienyl had a death rate of only 0.4 percent. The better than fifty percent mortality of the flies treated with the base oil containing iron dicyclopentadienyl is indicative of the insecticidal properties of naphthas containing a small amount of iron dicyclopentadienyl. Naturally, the amount of metallo cyclopentadienyl used in insecticidal compositions-will vary with the particular compound employed and also depends upon the particular insects for which the spray is intended. The amount of iron dicyclopentadienyl employed in insecticidal compositions intended for use on flies is between about 1.0 and 10.0 percent by weight.

Ya know, a greater than 50 % kill rate seems to be getting a bit sporty for the flies. The ol’ boys at Gulf were studying the suitability of a variety of ferrocene analogs for fuel additive application. What lead them to go from octane enhancement and smoke control to killing flies is not revealed in the patent.

Notice the nomenclature in the patent language. The word ferrocene is not mentioned. Looking at the timeline we see that the Gulf ‘685 patent was filed April 21, 1952, not long after the publication of this curious iron cyclopentadienyl compound by two groups, Kealy & Pauson on 12/15/51, and Miller, Tebboth, and Tremaine on 1/1/52. Though Pauson and Keely published first, an examination of the papers show that Miller, Tebboth, and Tremaine were first to submit- July 11, 1951 vs August 4, 1951 for Pauson and Kealy.

The day before Gulf filed the patent application, April 20, 1952, a groundbreaking paper by Wilkinson, Rosenblum, Whiting, and Woodward was published on the proposed structure of iron bis-cyclopentadienyl. It is reported that the name ferrocene was invented by Mark Whiting, a student of R.B. Woodward and coauthor of the 1952 paper in JACS. The name derives from the ferrous ion and the aromatic (“benzene”) nature of the cyclopentadienyl ligands.

The curious structure was proposed largely on the strength of a single C-H IR band at 3.25 μ. Since all of the C-H bonds appeared to be equivalent, the only structure compatible with the formula, charges and symmetry was the famous η5 (eta five) sandwich structure. Later the word metallocene finds use for this class of substances.

There is disagreement as to some of the details outlined above. An excellent article by Pierre Lazlo and Roald Hoffmann navigates some of the narrower channels in the history of ferrocene. It is well worth the read. Lazlo & Hoffmann suggest that Woodward is thought to have conceived the sandwich structure.

Ferrocene and derivatives would soon prove useful in many areas. A more obscure application is found in the field of rocket propellant additives and function as burn rate stabilizers. In fact, certain ferrocene derivatives appear on the US Munitions List, 22 CFR 121.1, Category V, (f)(4) Ferrocene Derivatives. A good overview of ferrocene and other metallocenes can be found in Wikipedia.

Circling back to the beginning of this piece, the patent application for Gulf ‘685 was filed 4/21/52, only 4 months after the publication on 12/15/51 of the Pauson & Kealy paper and two weeks later the Miller, et al., paper on 1/1/52. In the 4 months between Pauson & Kealy and the Gulf patent filing, two independent groups had published papers reporting the preparation of iron dicyclopentadienyl by different methods, a Harvard group had postulated a structure for the compound using IR data and a novel bonding type, and the Gulf R&D group had produced various analogues for testing as fuel additives. In this short time interval, the first organo-iron compound was taken from a literature source through industrial R&D and a patent application. As a premium, Gulf even determined that it had insecticidal properties. Much happened in a short time.

 


Wilkinson, Rosenblum, Whiting, and Woodward J. Am. Chem. Soc., 1952, 74 (8), pp 2125–2126. DOI: 10.1021/ja01128a527

Kealy and Pauson, Nature, 168, 1039 (1951). Received Aug. 7, 1951.  DOI: 10.1038/1681039b0

Miller, Tebboth, and Tremaine J. Chem. Soc., 1952,0, 632-635. Received July 11, 1951. DOI: 10.1039/JR9520000632

Laszlo P., Hoffmann R. ACIEE, 2000 Jan; 39(1):123-124.  DOI: 10.1002/(SICI)1521-3773(20000103)39:1<123::AID-ANIE123>3.0.CO;2-Z

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