Patent ID: 7638657

Claim:
A process for the preparation of 3-[5′-(3,4-bis(hydroxymethyl)benzyloxy)-2′-ethyl-2-propylbiphenyl-4-yl]pentan-3-ol having the structure: which comprises the following 4 stages: a) converting 1-(4-hydroxy-3-propylphenyl)propan-1-one into trifluoromethanesulfonic acid 4-propionyl-2-(n-propyl)phenyl ester, followed by reacting same with 2-ethyl-5-methoxyphenylboronic acid; b) demethylation of 1-(2′-ethyl-5′-methoxy-2-propylbiphenyl-4-yl)propan-1-one by heating with an excess of pyridine salts; c) converting 1-(2′-ethyl-5′-hydroxy-2-propylbiphenyl-4-yl)propan-1-one into 6-ethyl-4′-(1-ethyl-1-hydroxypropyl)-2′-propylbiphenyl-3-ol by reaction with ethylmagnesium bromide or with ethyllithium; and d) condensation of 6-ethyl-4′-(1-ethyl-1-hydroxypropyl)-2′-propylbiphenyl-3-ol with dimethyl 4-(bromomethyl)phthalate, followed in situ by a reduction reaction with lithium borohydride.