Heavily-substituted 1-aryltetralins and 1-arylindanes were prepared in a highly stereoselective manner using a two-step sequence. Addition of t-butyl benzyl sulfoxides to unsaturated carbonyl compounds gave conjugate adducts with high diastereoselectivity. Treatment of the adducts with SnCl 4 generated benzyl carbocations which reacted intramolecularly with suitably-positioned aromatic rings to give tetralins and indanes, again with high diastereoselectivity.

A Novel Method for the Stereoselective Synthesis of Tetralins and Indanes.-A novel annulation strategy via LDA-mediated diastereoselective conjugate addition of sulfones (I) to α,β-unsaturated carbonyl compounds (II), (V) and (VIII) followed by SnCl 4 -mediated cyclization is described. -(APPELBE, ZELDA; CASEY, MIKE; KEAVENEY, CLAIRE M.; KELLEY, CORNELIUS J.; Synlett (2002) 9, 1404-1408; Dep. Chem., Univ. Coll., Belfield, Dublin 4, Ire.; EN)