79239-44-4Relevant academic research and scientific papers
Sigmatropic Rearrangements of Some Allylic Oxosulphonium Ylides. A Route to Trienes and Azatrienes, and Their cyclic Isomers
Faragher, Roy,Gilchrist, Thomas L.,Southon, Ian W.
, p. 2352 - 2356 (2007/10/02)
The imidoyl-substituted oxosulphonium ylides (2) reacted with dimethyl acetylenedicarboxylate and with dibenzoylacetylene by conjugate addition.The resulting allylic oxosulphonium ylides underwent sigmatropic tearrangement at room temperature or below, to give the sulphoxides (3).These sulphoxides readily lost methanesulphinic acid when heated at 80 deg C, and gave the dihydropyridines (4).These reactions are presumed to go by way of intermediate azatrienes (6).The stabilised oxosulphonium ylides (7) reacted with dimethyl acetylenedicarboxylate by a similar sequence which gave the isolable trienones underwent electrocyclic ring-closure when heated in xylene.
