Synthesis of 1,3,4-Oxadiazoles from Carboxylic Hydrazides and of 1,2-Oxazin-6-ones from α-(Hydroxyimino)carboxylic Esters with Keteneylidene Triphenylphosphorane

Article abstract of DOI:10.1055/s-1997-766

In a one-pot procedure 1,3,4-oxadiazoles 8 are prepared from carboxylic hydrazides 2 and keteneylidene triphenylphosphorane 1 via an untypical intermolecular Wittig olefination of a carbamate type carbonyl group. Under similar conditions, reaction of 1 an