Patent ID: 7872160

Claim:
A single pot process for the regioselective synthesis of the neolignan 3(R)-ethyl-2(S)-methyl-3-(2″,4″,5″-trimethoxyphenyl)-1-(2′,4′,5′-trimethoxyphenyl)propane from asarones which comprises mixing β asarone with montmorillonite clay catalyst in a ratio of 1.0:0.1 to 1.0:0.5 (w/w) in a hydrocarbon solvent and subjecting said solution mixture to microwave irradiation for a period of 5-20 minutes, removing the catalyst by filtration and evaporating the solvent from the filtrate under reduced pressure to obtain the residue, subjecting said residue to combiflash chromatography and eluting it with a mixture of n-hexane and ethyl acetate to obtain the neolignan product.