Synthese heterocyclischer Dialkine und deren Umsetzung mit CpCo(CO)2

Synthesis of Heterocyclic Diynes and their Reaction with CpCo(CO)2 The preparation of the heterocyclic diynes 1,6‐dithia‐3,8‐cyclodecadiyne (1b), thia‐3,8‐cyclodecadiyne (11), 1‐thia‐6‐selana‐3,8‐cyclodecadiyne (12), oxa‐3,8‐cyclodecadiyne (13), 1,6‐dioxa‐3,8‐cyclodecadiyne (14), 1‐oxa‐6‐thia‐3,8‐cyclodecadiyne (15), 1,6‐diselena‐3,8‐cyclodecadiyne (26), thia‐3,9‐cyclounde‐cadiyne (22a), thia‐3,13‐cyclopentadecadiyne (22b) and its selena analogues 23a, 23b is described. The thia and monoselena compounds are obtained by a thia‐ or selenacyclization of the corresponding dibromides. Compound 26 has been obtained by a Misumi coupling reaction. The thiacycloalkadiynes of medium‐sized rings (10, 11) react with CpCo(CO)2 to yield [2,2](2,5)thiophenophane derivatives. Acyclic thiadialkynes or thiacycloalkadiynes of larger ring size (22b) with CpCo(CO)2 by [2 + 2 + 2] cycloaddition.