Template synthesis, structure and electropolymerization of the 2-thiopheneboron-capped cobalt(II) clathrochelates

► Thiopheneboron-capped clathrochelate coablt(II) tris-dioximates were obtained. ► Electropolymerization of their apical substituents afforded polymeric clathrochelates. ► The structures of the cobalt(II) clathrochelates undergo Jahn-Teller distortion. ► Hexachlorine-containing Co(II) clathrochelate undergo spin transition 1/2 ↔ 3/2 ► Co(II) clathrochelates and the electropolymers are electrocatalysts for H2 production.