Diastereoselective reaction of 1-(arylsulfinyl)-2-naphthaldehydes

Reactions of various 1-sulfinyl-2-naphthaldehydes with Grignard reagents were examined. The naphthaldehyde having the 2,4,6-triisopropylphenylsulfinyl group gave the product with high stereoselectivity, possibly derived from the predominant rotamer around the C–S axis. The reaction of the chiral sulfinylnaphthaldehyde with PhMgBr and subsequent elimination of the sulfinyl group gave the enantiomerically pure 2-naphthyl carbinol.