| Abstract
| - The reaction of TaMe3Cl2with the lithium salt of tetramethylpyrrole (Li−TMP) led to theformation of (η5-TMP)TaMe3Cl (1). Reactions of1 with a series of anionic ligands have been carried out toform products of theformula (η5-TMP)TaMe3X, where X = SR,Me, pyrrolyl, or indolyl. Crystals of(η5-TMP)TaMe3(indolyl)(5),were isolated in space group P21/cwith a = 8.957(2) Å, b = 28.540(6)Å, c = 14.695(3) Å, β = 99.40(3)°,V= 3706.1(14) Å3, and Z = 8. Thestructure confirmed the η5-bonding mode of thetetramethylpyrrolyl ligandand the η1-N-coordination mode of the indolyl ligand.Thederivatives (η5-TMP)TaMe3X showedlimited stability,and decomposition products which formed in toluene solutions at roomtemperature have been identified in somecases. The reaction of(η5-TMP)TaMe3(pyrrolyl) withhydrogen (2−3 atm) in benzene-d6 solution atroomtemperature was studied. The stoichiometric formation ofcyclohexane-d6 by hydrogenation of an equivalentofsolvent was confirmed by 1H and 13C NMR and gaschromatographic/mass spectroscopic data. Thecharacteristicsand scope of the room temperature arene hydrogenation process arediscussed.
- Complexes of the formula(η5-TMP)TaMe3X, where TMP =tetramethylpyrrolyl and X = Cl, Me, pyrrolyl, or indolyl, have beensynthesized starting from TaMe3Cl2 andLiTMP. The products have been characterized and their stabilitiesand reactivities studied. A solution of(η5-TMP)TaMe3(NC4H4)in benzene-d6 was found to react with hydrogenat room temperature to formcyclohexane-d6.
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