Archive for April, 2010
Friday, April 16th, 2010
Some molecules, when you first see them, just intrigue. So it was with carbobenzene, the synthesis of a derivative of which was recently achieved by Remi Chauvin and co-workers[1]. Two additional carbon atoms have been inserted into each of the six C-C bonds in benzene.
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References
- C. Saccavini, C. Sui‐Seng, L. Maurette, C. Lepetit, S. Soula, C. Zou, B. Donnadieu, and R. Chauvin, "Functional [6]Pericyclynes: Aromatization to Substituted <i>carbo</i>‐Benzenes", Chemistry – A European Journal, vol. 13, pp. 4914-4931, 2007. https://doi.org/10.1002/chem.200601193
Tags:aromatic systems, General, http, Missouri, Remi Chauvin
Posted in General | 4 Comments »
Tuesday, April 6th, 2010
Here I offer another spin-off from writing a lecture course on conformational analysis. This is the famous example of why 1,2-difluoroethane adopts a gauche rather than antiperiplanar conformation.
The gauche and antiperiplanar conformations of 1,2-difluoroethane
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Tags:appropriate algorithms, conformational analysis, energy gap, Here I, interaction energy, Interesting chemistry, spin-off
Posted in Interesting chemistry | 14 Comments »
Friday, April 2nd, 2010
One of the (not a few) pleasures of working in a university is the occasional opportunity that arises to give a new lecture course to students. New is not quite the correct word, since the topic I have acquired is Conformational analysis. The original course at Imperial College was delivered by Derek Barton himself about 50 years ago (for articles written by him on the topic[1] or the original[2] and so I have had an opportunity to see how the topic has evolved since then, and perhaps apply some quantitative quantum mechanical interpretations unavailable to Barton himself.
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References
- D.H.R. Barton, "The Principles of Conformational Analysis", Science, vol. 169, pp. 539-544, 1970. https://doi.org/10.1126/science.169.3945.539
- D.H.R. Barton, and R.C. Cookson, "The principles of conformational analysis", Quarterly Reviews, Chemical Society, vol. 10, pp. 44, 1956. https://doi.org/10.1039/qr9561000044
Tags:10.1021, conformational analysis, Derek Barton, energy maxima, Imperial College, Interesting chemistry, lower energy, overall energy, potential energy surface, Tutorial material
Posted in Interesting chemistry | 11 Comments »