Reactivity of differentially substituted bis(diazo) esters in rhodium(II) mediated O-H insertion reactions

Abstract

Selective catalysed decompositions of one diazo group in the presence of another are discussed. A range of bis(diazo) compounds was prepared in which the two diazo groups are differentially substituted. Rhodium(II) acetate catalysed decomposition in the presence of methanol resulted in exclusive O-H insertion reaction at the more reactive diazo group, the less reactive diazophosphonate remaining intact. With the more active rhodium(II) trifluoroacetamide as catalyst, both diazo groups decomposed simultaneously.