Abstract:
3-Benzylideneindoline-2-thione, formed by the condensation of indoline-2-thione with benzaldehyde, undergoes an unexpectedly facile [4 + 2] cycloaddition in solution to yield an unsymmetrical dimer 7. The structure of this dimer, elucidated by NMR spectroscopy and confirmed by X-ray crystallography, is described, and the mechanism and stereospecificity of this reaction is discussed.
