On the nitrile effect in L-rhamnopyranosylation.
It is shown that the use of 5% acetonitrile or propionitrile in dichloromethane functions to increase the beta-selectivity of a number of L-rhamnopyranosylation reactions conducted by the thioglycoside method with activation by the 1-benzenesulfinyl piperidine/trifluoromethanesulfonic anhydride couple. The use of more significant quantities of acetonitrile or propionitrile results in the formation of complex reaction mixtures containing little coupled product, but from which Ritter-type products can be isolated.
Crich
David
D
Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL 60607-7061, USA. dcrich@uic.edu
Patel
Mitesh
M
D000097:Acetonitriles / Q000737:chemistry; D006031:Glycosylation; D009570:Nitriles / Q000737:chemistry*; D012210:Rhamnose / Q000737:chemistry*
D000097:Acetonitriles; D009570:Nitriles; C005557:propionitrile; D012210:Rhamnose; C032159:acetonitrile