Bis(methylthio)tetracenes: synthesis, crystal-packing structures, and OFET properties.

5,12-Bis(methylthio)tetracene (2) and 5,11-bis(methylthio)tetracene (3) were synthesized. DFT calculations indicate that the HOMO and LUMO energy levels of 2 and 3 are lowered by 0.13-0.

2,8- and 2,9-Diboryltetracenes as useful building blocks for extended pi-conjugated tetracenes.

Ir-catalyzed direct diborylation of tetracene gave a 1:1 mixture of 2,8- and 2,9-bis[(pinacolato)boryl]tetracenes, which were separated by recrystallization. These diboryltetracenes are useful building blocks for the regiospecific synthesis of extended pi-conjugated tetracenes directed to semiconductors for organic field-effect transistors (OFETs). Syntheses of thiophene-tetracene-thiophene, thiophene-tetracene-bithiophene-tetracene-thiophene, and thiophene-tetracene-anthracene-tetracene-thiophene pi-systems have been achieved on the basis of the 2,8- and 2,9-diboryltetracenes.