9-(2-Oxo-1-azetidinyl)-10,10-dimethyl-9,10-dihydro-10-sila-2-azaanthracenes

9-(3-Methyl-3-bromo-2-oxo-1-azetidinyl)-10,10-dimethyl-9,10-dihydro-10-sila-2-azaanthracene was obtained in the form of a mixture of two diastereomers by intramolecular cyclization of the corresponding 9-(α,Β-dibromoisobutyrylamino)dihydrosilaazaanthracene in the presence of sodium hydride, as well as Triton B. It was established by two-dimensional nuclear Overhauser effect (NOE) spectroscopy that the azetidinyl substituent in the 9 position has a pseudoaxial orientation vis-à-vis a boat conformation of the central silicon-containing ring. © 1991 Plenum Publishing Corporation.