Palladium-Catalyzed C-H Arylation of Thieno[2,3-b]thiophene: An Approach to Novel 2,5-Diaryl/Heteroaryl Thieno[2,3-b]thiophenes - Mashraqui, Sabir H; Ashraf, Mohamed; Ghadigaonkar, Shailesh G (Synlett, 2006)