Reactions of dialkyl (3,5-di-tert-butyl-4-oxocyclohex-2,5-dienylidenemethyl)phosphonates with alcohols and some transformations of the adducts

Abstract

Reactions of dialkyl [(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)methyl]phosphonates with butyl, benzyl and propargyl alcohols in the presence of catalytic amounts of trifluoromethanesulfonic acid resulted in the formation of nucleophilic 1,6-addition products. Azide-alkyne cycloaddition reaction of dimethyl (3,5-di-tert-butyl-4-hydroxyphenyl)(prop-2-ynyloxy)methylphosphonate with benzyl azide and 1,3-bis-(2-azidoethoxy)benzene in the presence of copper sulfate and sodium ascorbate afforded 1,2,3-triazoles with sterically hindered phenol fragments.