US7872160: Single pot process for the regioselective synthesis of neolignan fr+B53amework asarones

The invention provides a single pot process for the regioselective synthesis of neolignane framework [3(R)-Ethyl-2(S)-methyl-3-(2'',4'',5''-trimethoxyphenyl)-1-(2',4',5'-trim- ethoxyphenyl) propane from toxic ?-isomer rich asarone using montmorillonite acidic clay by employing microwave organic reaction enhancement (MORE) chemistry. This may be useful as a versatile synthetic protocol for the synthesis of a large number of lignan and neolignane frameworks.