Record-breaking remote stereocontrol
Remote stereocontrol, or the ability to control the formation of chiral centres over long molecular distances, has long been a forte of organic chemistry in Manchester.
Jonathan Clayden and his group have for 10 years held the world record for remote stereocontrol (over a distance of 22 bonds, published in Nature in 2004). Now, in work published in Angewandte Chemie, post-doc Liam Byrne from Jonathan’s group has shattered the group’s own record by using a peptide-like helical chain to mediate the communication of stereochemical information. Reactions of these helical compounds display remote stereocontrol over at least 60 bonds, a distance of about 4 nm. The analysis of compounds with such remotely related stereogenic centres poses a specific challenge, met by Prof Gareth Morris and his post-doc Ralph Adams, whose pure shift NMR pulse sequences were used to determine accurately the ratios of reaction products.
The remotely stereocontrolled reactions can be read about in Angewandte Chemie 2014, 53, 131-133 (doi 10.1002/anie.201308264), and the use of pure shift NMR to analyse the products in Chem Commun. 2014 in press (doi 10.1039/C3CC49659G)