Benzothiazines in Synthesis: A Route to Chiral Cyclobutanes

Abstract

Using enantiomerically pure benzothiazines as templates, enantiomerically pure cyclobutanes were prepared. Such compounds are potentially interesting synthetic intermediates. The sequence developed for the preparation of these compounds, as well as some of their chemistry, is described.

Key words

benzothiazines - enantiomerically pure - cyclobutanes - stereoselective - metalation

References

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9

Crystallographic data (excluding structure factors) for some structures reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication numbers CCDC 658446 (5e), 658447 (5g), 672249 (6a), 658448 (6c), 658567 (6e), 658449 (7), and 658450 (sulfone of 7). Copies of the data can be obtained, free of charge, on application to CCDC, 12 Union Road, Cambridge CB2 1EZ, UK [Fax: [phone]; E-mail: [e-mail]].