Palladium-mediated synthesis of 1,1,2-triarylethanes. Application to the synthesis of CDP-840

Abstract A three-step protocol toward 1,1,2-triarylethanes 1 starting with β-ketosulfones 2 is developed. A facile process is carried out for the (1) reduction of 2 with NaBH 4 , (2) BF 3 ·OEt 2 -mediated Friedel-Crafts reactions of the resulting β-hydroxy sulfones 3 , and (3) palladium-catalyzed desulfonylative cross-coupling of the corresponding 5 with aryl iodides 4 in the presence of t -BuOK under warming DMF in acceptable yields. A facile synthesis of CDP-840 ( 1v ) has been studied.