Studies on Diphenyl Ether Derivatives. VIII. NMR Spectra and Conformational Structure of Dibenz[b, g][1, 5]oxazocine and Thiazocine Derivatives and Their Mass Spectra

Abstract

The NMR spectra of 6-substituted 6, 7-dihydro-5H-dibenz[b, g][1, 5]oxazocine and thiazocine derivatives (1) and the sulfoxides or sulfones (6) and the bimolecular sixteen membered ring compounds (2) were reported. The methylene protons at 5 and 7-position of the ring of 6 appeared as a AB system quartet. All ring methylene protons in 2 gave a singlet. The temperature dependent coalescence and splitting of the singals was observed in 1. At low temperature the 5, 7-methylene protons in thr ring of 1 gave a AB quartet and a singlet. From these facts it was suggested that 1 was amixture of the conformational isomer A and B in Fig. 8 and they could not freely rotate each other even at room temperaute. 6 existed only as the structure A. The Mass spectra of them were also reported.