Synthesis and X-ray single-crystal structure study of 5,5′-bis(silyl)-functionalized 3,3′-dibromo-2,2′-dithiophenes

A high-yield synthesis toward 5,5'-bis(silyl)-functionalized 3,3'-dibromo-2,2'-dithiophenes with very efficient work-up procedure is presented. The molecular structures of two silyl functionalized dibromo-dithiophenes in the solid state have been determined to investigate the structural influences of different functional groups on the degree of pi-conjugation within the dithiophene moieties, as well as their packing properties. The planar alignment of the tert-butyldimethylsilyl-functionalized dibromo-dithiophene shows a significantly higher degree of conjugation of the pi-system with a more favorable molecular packing than the skewed arrangement of the triisopropylsilyl-substituted species. Copyright (c) 2005 John Wiley & Sons, Ltd.