Orthogonally functionalized naphthodithiophenes: selective protection and borylation.

Selective functionalization protocols of naphtho[1,2-b;5,6-b']dithiophene (NDT3) by combining protection of the thiophene α-positions and direct borylation on the naphthalene core are described, which allows synthesizing a number of new NDT3-based building blocks with various substituents and isomeric NDT3-based polymers with different main chain structures. The same protocol is applicable to other isomeric naphthodithiophenes (NDTs), which affords a set of key building blocks for the development of elaborated functional π-materials.