Preparation of Hetero‐π‐Conjugated Compounds by Double Nucleophilic Addition to Haloalkynes and C−H Cyclization

When a mixture containing 1‐halo‐1‐alkyne, a dinucleophilic agent, and a base (Cs 2 CO 3 or K 3 PO 4 ) was heated in DMF, regio‐ and stereo‐selective nucleophilic addition of the dinucleophilic agent to the acetylenes occurred. This reaction yielded ( Z , Z )‐bis(haloalkene), which subsequently underwent Pd‐catalyzed cyclization through C−H bond activation, resulting in the formation of two‐oxygen‐ or ‐nitrogen‐containing hetero‐π‐conjugated compounds. N ‐(5‐Hydroxynaphthalen‐1‐yl)methanesulfonamide was treated with 2‐phenyl‐1‐chloroethyne followed by 1‐chloro‐1‐hexadecyne. After these reactions, Pd‐catalyzed double C−H cyclization was employed to produce 1 H ‐2‐phenyl‐7‐tetradecylbenzofuro[7,6‐ g ]indole. Notably, this compound transformed into a fan‐shaped structure at 86 °C and transitioned into a smectic A phase characterized by a layered structure.