Synthesis of 2,3,4Trisubstituted Thiochromanes using an Organocatalytic Enantioselective Tandem Michael–Henry Reaction

Enantioenriched 2,3,4trisubstituted thiochromanes have been synthesized by using a cupreinecatalyzed tandem Michael addition–Henry reaction between 2mercaptobenzaldehydes and βnitrostyrenes. Good diastereoselectivities and enantioselectivities were obtained for the title compounds, which may be further improved through a single recrystallization up to 98% deand>99% ee.