This invention relates to a process for the preparation of (-) 3R, 4R - trans -2,2-dialkyl -3- substituted phenyl-4- (hydroxy substituted phenyl)- substituted chromans. The product is used as key intermediates for the preparation of tissue selective estrogens as pharmaceuticals. The product of the structure 2, where in R1 and R4 are individually hydrogen, hydroxy, halogens, C1-6 alkyl, C1-6 alkoxy, R2, R3, are individually hydrogen, C1-6 alkyl and R5 is hydrogen, halogen, nitro, cyano, C1-6 alkyl or cyclic alkyloxy, is prepared by treating 3R, 4R- trans - 2,2-dialkyl -3- substituted phenyl-4-(ω-aminoalkoxy substituted phenyl)- substituted chroman derivatives of structure 3 where in R1, R2, R3, R4 and R5 are as stated above and R6 is a methyl iodide salt of a substituted amino alkoxy group, with an inorganic base 3R, 4R- trans - 2,2-dialkyl -3- substituted phenyl-4- of formula 3 with inorganic base, , isolating the hydroxide salt and reacting the isolated hydroxide salt with cyclic amines in a high boiling solvent at a temperature in the range of 80°C to 200°C for a period of 5 minutes to 8 hrs or insitu conversion of methyliodide salt to desired compound of structure 2 using above stated methodology.
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