Henry Rzepa's Blog Chemistry with a twist

March 5, 2017

A nice example of open data (in London).

Living in London, travelling using public transport is often the best way to get around. Before setting out on a journey one checks the status of the network. Doing so today I came across this page: our open data from Transport for London. 

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December 11, 2015

The atom and the molecule: A one-day symposium on 23 March, 2016 celebrating Gilbert N. Lewis.

You might have noticed the occasional reference here to the upcoming centenary of the publication of Gilbert N. Lewis’ famous article entitled “The atom and the molecule“.[1] A symposium exploring his scientific impact and legacy will be held in London on March 23, 2016, exactly 70 years to the day since his death. A list of the speakers and their titles is shown below; there is no attendance fee, but you must register as per the instructions below.

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References

  1. G.N. Lewis, "THE ATOM AND THE MOLECULE.", Journal of the American Chemical Society, vol. 38, pp. 762-785, 1916. http://dx.doi.org/10.1021/ja02261a002

December 22, 2014

Chemistry in the early 1960s: a reminiscence.

I started chemistry with a boxed set in 1962. In those days they contained serious amounts of chemicals, but I very soon ran out of most of them. Two discoveries turned what might have been a typical discarded christmas present into a lifelong career and hobby.

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November 12, 2014

A computed mechanistic pathway for the formation of an amide from an acid and an amine in non-polar solution.

In London, one has the pleasures of attending occasional one day meetings at the Burlington House, home of the Royal Society of Chemistry. On November 5th this year, there was an excellent meeting on the topic of Challenges in Catalysisand you can see the speakers and (some of) their slides here. One talk on the topic of Direct amide formation – the issues, the art, the industrial application by Dave Jackson caught my interest. He asked whether an amide could be formed directly from a carboxylic acid and an amine without the intervention of an explicit catalyst. The answer involved noting that the carboxylic acid was itself a catalyst in the process, and a full mechanistic exploration of this aspect can be found in an article published in collaboration with Andy Whiting's group at Durham.[1] My after-thoughts in the pub centered around the recollection that I had written some blog posts about the reaction between hydroxylamine and propanone. Might there be any similarity between the two mechanisms?

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References

  1. H. Charville, D.A. Jackson, G. Hodges, A. Whiting, and M.R. Wilson, "The Uncatalyzed Direct Amide Formation Reaction - Mechanism Studies and the Key Role of Carboxylic Acid H-Bonding", European Journal of Organic Chemistry, vol. 2011, pp. 5981-5990, 2011. http://dx.doi.org/10.1002/ejoc.201100714

June 5, 2013

Computers 1967-2013: a personal perspective. Part 5. Network bandwidth.

In a time of change, we often do not notice that Δ = ∫δ. Here I am thinking of network bandwidth, and my personal experience of it over a 46 year period.

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July 12, 2012

More joining up of pieces. Stereocontrol in the ring opening of cyclopropenes.

Years ago, I was travelling from Cambridge to London on a train. I found myself sitting next to a chemist, and (as chemists do), he scribbled the following on a piece of paper. When I got to work the next day Vera (my student) was unleashed on the problem, and our thoughts were published[1]. That was then.

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References

  1. M.S. Baird, J.R. Al Dulayymi, H.S. Rzepa, and V. Thoss, "An unusual example of stereoelectronic control in the ring opening of 3,3-disubstituted 1,2-dichlorocyclopropenes", Journal of the Chemical Society, Chemical Communications, pp. 1323, 1992. http://dx.doi.org/10.1039/C39920001323

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