Df. Oshea et Jt. Sharp, A ROUTE TO DIHYDRO[2]BENZOOXEPINO[4,5-C]PYRIDINES AND DIHYDROTHIENO[D][2]BENZOOXEPINES VIA THE 1.7-ELECTROCYCLIZATION OF CARBONYL YLIDES, Journal of the Chemical Society. Perkin transactions. I, (6), 1996, pp. 515-518
The cyclisation of diene-conjugated carbonyl ylides of the general typ
e 2, in which the alpha,beta;gamma,delta diene function is formed by a
benzene ring and either a thiophene or pyridine ring provides a new r
oute to some hetero-fused dihydrobenzooxepines. The oxirane precursors
for the carbonyl ylides were synthesised in a two-step scheme from re
adily available reactants.