Aluminum Compounds Containing eta(1-) and/or eta(5)-Bidentate Dianionic Pyrrolyl-Methylamide Ligands

作者：Chen Ya Chi; Lin Che Yu; Li Chun Yin; Huang Jui Hsien^*; Chang Ling Chueh; Lee Ting Yu

来源：Chemistry - A European Journal, 2008, 14(31): 9747-9753.

DOI：10.1002/chem.200800679

• aluminum
• caprolactone
• lithium
• ring-opening polymerization
• sandwich complexes

A series of dialuminum compounds have been synthesized and their reactivity and application for lactide polymerization have been studied. The reaction of AIH(3)center dot NMe3 with [C4H3NH(2-CH(2)NHtBu)] in diethyl ether generated a dimeric aluminum hydride compound, [{[C4H3N(2-CH(2)NtBu)]AIH)(2)] (1). The structure of 1 was confirmed by spectroscopy of a deuterated analogue of 1 with an Al-D function. Direct treatment of [C4H3NH(2-CH(2)NHtBu)] with LiAIH(4) in diethyl ether resulted in colorless crystals of [{Li[mu-eta(1):eta(5)-C4H3N(2-CH(2)NtBu)](2)Al}(2)] (2) in 80% yield after recrystallization from a toluene soluton . The mu-eta(1):eta(5)-pyrrolyl protons exhibit high-field shifts at delta=5.73,6.15, and 6.72 comparable to a similar eta(5) bonding mode in the literature. Treatment of 1 with 1 eqiv acetone oxide or acetone in dichloromethane gave [C4H3NH(2-CH(2)NHtBu)]Al-[kappa O,kappa N-(ON=CMe2)]}] (3) and [C4H3NH(2-CH(2)NHtBu)]Al-[kappa O,kappa N-(ON=CMe2)]}] (4) in 67% and 60% yield. respectively. Compounds 1-4 have been characterized by X-ray diffractometry and were used as catalysts for epsilon-caprolactone polymerization.

• 出版日期2008