On the synthesis of α-amino sulfoxides.
A synthetic study on the preparation of N-Boc α-amino sulfoxides has revealed an unexpected instability which is believed to be due to α-elimination of the sulfoxide to give an iminium ion. Full synthetic details are reported on two main synthetic routes: lithiation and sulfinate trapping of N-Boc heterocycles and oxidation of N-Boc α-amino sulfides. Six novel α-amino sulfoxides were successfully prepared and isolated. It is speculated that four other α-amino sulfoxides were synthesised but could not be isolated due to their propensity to α-eliminate the sulfoxide. Ultimately, a stable, cyclic N-Boc α-amino sulfoxide was prepared and this successful synthesis relied on the α-amino sulfoxide being part of a bicyclic [3.1.0] fused ring system that could not undergo α-elimination of the sulfoxide.
Department of Chemistry, University of York, Heslington, York YO10 5DD, UK. peter.obrien@york.ac.uk.
Peter J
PJ
Rayner
Giacomo
G
Gelardi
Peter
P
O'Brien
Richard A J
RA
Horan
David C
DC
Blakemore
D010084:Oxidation-Reduction; D013440:Sulfides / Q000737:chemistry; D013450:Sulfones / Q000737:chemistry; D013454:Sulfoxides / Q000138:chemical synthesis* / Q000737:chemistry
D013440:Sulfides; D013450:Sulfones; D013454:Sulfoxides