ORGN 28

Previously, our group reported the addition of α-alkoxyalkyl radicals to N-tosylimines. In continuation with this study, we envisioned an asymmetric variant of the reaction by utilizing enantiopure N-sulfinylimine substrates.

To this end, addition of dimethylzinc (3 mmol) to a solution of (S)-(+)-N-(benzylidene)-p-toluenesulfinamide (1) (1 mmol) and boron trifluoride etherate (1 mmol) in 4,4,5,5-tetramethyl-1,3-dioxolane (18.3 mL) with continuous introduction of air (0.5 mL/h), at ambient temperature resulted in complete consumption of N-sulfinylimine 1 after 2 h. Treatment of the crude material with m-chloroperbenzoic acid (1 mmol) gave adduct 2 in excellent yield and good ee.