Abstract
Reactions of readily available and stable 1-(alpha-alkoxyalkyl)benzotriazoles type 9a, b and 10a-d with a variety of silyl enol ethers 11 or 1,3-dicarbonyl compounds 13 give the expected ketones 12a-l (60-92%), beta-keto esters 14a, b (62-67%), and malonates 14c,d (79-88%) in which a tetrahydrofuran or tetrahydropyran moiety has been introduced at the a position. 1-(Benzotriazol-1-yl) alkyl esters 7 are converted by cyanide anion into cyanohydrin esters 15a-i (55-98%). (c) 2007 Published by Elsevier Ltd.