Alkali Metal Reduction of 1,2‐Bis[(2,6‐dibenzhydryl‐4‐methylphenyl)imino]acenaphthene (Ar BIG ‐bian) to Radical‐Anion

Coordination polymers derived from alkali metal complexes of redox-active ligands

Treatment solutions of (dpp-bian)M (dpp-bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene; M = Li, Na, K) with 4,4′-bipyridine (4,4′-bipy) affords coordination polymers [(dpp-bian)M(4,4′-bipy)m]n, (M = Li or K, m = 1; M = Na, m = 2).

Reduction of CO2 with Aluminum Hydrides Supported with Ar-BIAN Radical-Anions (Ar-BIAN = 1,2-Bis(arylimino)acenaphthene)

The reactions of H₂AlCl with [(dpp-Bian)Na(Et₂O)_n] and [(Ar^BIG-Bian)Na(THF)] produce respective aluminum hydrides supported by radical-anionic 1,2-bis(arylimino)acenaphthene ligands, [(dpp-Bian)AlH₂] (1) and [(Ar^BIG-Bian)AlH₂(THF)] (2) (dpp-Bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene); Ar^BIG-Bian = 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene). The reaction of 1 with CO₂ proceeds with reduction of both C═O bonds and results in diolate [{(dpp-Bian)Al(μ-O₂CH₂)}₂] (3). Complex 2 reacts with CO₂ to carbonate [{(Ar^BIG-Bian)Al(μ-OCH₂OCO₂)}₂] (4) that is a result of the insertion of CO₂ into the Al-O bond in diolate species formed initially. Aluminum monohydrides [(dpp-Bian)AlH(X)] (X = Cl, 5; Me, 6) react with CO₂ to form respective alumoxanes [{(dpp-Bian)AlX}₂(μ-O)] (X = Cl, 7 and X = Me, 8). Compounds 1-4, 7, and 8 have been characterized by ESR and IR spectroscopy, and their molecular structures have been determined by single-crystal X-ray analysis.