Here is another exploration of simple chemical concepts using crystal structures. Consider a simple diene: how does the central C-C bond length respond to the torsion angle between the two C=C bond...
Read It Review ItPreviously, I explored deviation from ideal tetrahedral arrangements of four carbon ligands around a central (sp 3) carbon using crystal structures. Now it is the turn of digonal (sp 1) and trigona...
Read It Review ItThe phenomenon of bond stretch isomerism, two isomers of a compound differing predominantly in just one bond length, is one of those chemical concepts that wax and occasionally wane. Here I explore...
Read It Review ItDerek Lowe has a recent post entitled " Another Funny-Looking Structure Comes Through". He cites a recent medchem article[1] in which the following acetal sub-structure appears in a promising drug ...
Read It Review ItThis question was posted on the CCL (computational chemistry list) by John McKelvey. Here, I give an answer in the form of a search of the CSD (crystal structure database). I was not sure if the qu...
Read It Review ItThe original strategic objective of my PhD researches in 1972-74 was to explore how primary kinetic hydrogen isotope effects might be influenced by the underlying structures of the transition state...
Read It Review ItEarlier I explored models for the heteroaromatic electrophilic protiodecarboxylation of an 3-substituted indole, focusing on the role of water as the proton transfer and delivery agent. Next, came ...
Read It Review ItThis is the third and final study deriving from my Ph.D.[1]. The first two topics dealt with the mechanism of heteroaromatic electrophilic attack using either a diazonium cation or a proton as elec...
Read It Review ItAnother mechanistic study we started in 1972[1] is here 40+ years on subjected to quantum mechanical scrutiny. The kinetics are again complex, the mechanism involving protonation‡ of the...
Read It Review ItThe BBC TV quiz series Mastermind was first broadcast in the UK in 1972, the same time I was starting to investigate the mechanism of diazocoupling to substituted indoles as part of my Ph.D. resear...
Read It Review ItSource: Wikipedia. CC-BY-SA April this year I blogged about an important SPARQL query for many chemists: getting CAS registry numbers from Wikidata. This is relevant for two reasons: CAS works ...
Read It Review It0000-0002-8635-8390 The anomeric effect is best known in sugars, occuring in sub-structures such as RO-C-OR. Its origins relate to how the lone pairs on each oxygen atom align with the adjacent C-O...
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