Ein-und mehrkernkomplexe des 9,10-dihydro-9,10-dimethyl-9,10-diboraanthracens

Article abstract of DOI:10.1016/S0022-328X(96)06217-1

A series of new transitionmetal complexes of 9,10-dihydro-9,10-dimethyl-9,10-diboraanthracene (1) was synthesized and characterized. Mono-, di-, and trinuclear species were isolated, indicating the diversity of the ligand properties of 1. The reaction of 1 with an excess of [CoCp(C₂H₄)₂] yields the known 18 VE sandwich complex [(CoCp)1] (2) and the new paramagnetic 32 VE triple-decker complex [(CoCp)₂1] (3). [RhCp(C₂H₄)₂] forms with 1 the 18 VE sandwich complex [(RhCp)1] (4). Two equivalents of [FeCp(C₈H₁₂)] and 1 yield the diamagnetic 30 VE triple-decker [(FeCp)₂1] (5) with the iron atoms η⁶ bifacially coordinated to the heterocycle. The dianion 1^2- reacts with [CoCp*Br]₂ to form [(CoCp*)₃1] (6) with three independent 18 VE metal centres. The reactions of 1^2- with [Ni(C₃H₅)Br]₂ and [Ni(C₄H₇)Br]₂ lead to the 30 VE triple-decker complexes [{Ni(C₃H₅)}₂1] (7a) and [{Ni(C₄H₇)}₂1] (7b) respectively. [Pd(C₈H₁₂)₂] and [Pt(C₈H₁₂)₂] yield in the reaction with 1 the 18 VE complexes [Pd(C₈H₁₂)1] (8) and [Pt(C₈H₁₂)1] (9) respectively. The complex [Ni{(C₆H₅)₂PCH₂}₂1] (10) is generated by reacting 1^2- with [Ni{(C₆H₅)₂PCH₂}₂Cl₂]. Two equivalents of the radical anion 1^- and Ni²⁺ form the labile 18 VE sandwich [Ni(1)₂] (11). The constitutions of the new complexes have been derived from spectroscopic data and elemental analyses, and were confirmed by X-ray structure analyses for 5, 6, 7a, 8, 9, and 10.