Formation of a cyclooctatetraenylsamarium(iii) inverse sandwich that ring-opens tetrahydrofuran

Abstract

Reductive trapping of the cyclooctatetraenyl dianion (COT²⁻) by treatment of [Sm(DippForm)₂(thf)₂] (DippFormH = N,N′-bis(2,6-diisopropylphenyl)formamidine; thf = tetrahydrofuran) with 1,3,5,7-cyclooctatetraene (C₈H₈) in toluene yields an inverse sandwich dinuclear complex [Sm₂(DippForm)₄(COT)] (1), but [Sm(DippForm)(COT)(thf)₂] (2) and [Sm(DippForm)₂(O-C₄H₈-DippForm)(thf)] (3) in thf, and 1 yields 2 and 3 on treatment with thf.