Molybdenum Triamidoamine Complexes that Contain Hexa-tert-butylterphenyl, Hexamethylterphenyl, or p-Bromohexaisopropylterphenyl Substituents. An Examination of Some Catalyst Variations f

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• 作者：Vincent Ritleng ; Dmitry V. Yandulov ; Walter W. Weare ; Richard R. Schrock ; Adam S. Hock ; and William M. Davis
• 刊名：Journal of the American Chemical Society
• 出版年：2004
• 出版时间：May 19, 2004
• 年：2004
• 卷：126
• 期：19
• 页码：6150 - 6163
• 全文大小：257K
• 年卷期：v.126,no.19(May 19, 2004)
• ISSN：1520-5126

文摘

Three new tetramines, (ArNHCH₂CH₂)₃N, have been synthesized in which Ar = 3,5-(2,4,6-t-Bu₃C₆H₂)₂C₆H₃ (H₃[HTBTN₃N]), 3,5-(2,4,6-Me₃C₆H₂)₂C₆H₃ (H₃[HMTN₃N]), or 4-Br-3,5-(2,4,6-i-Pr₃C₆H₂)₂C₆H₂(H₃[pBrHIPTN₃N]). The diarylated tetramine, {3,5-(2,4,6-t-Bu₃C₆H₂)₂C₆H₃NHCH₂CH₂}₂NCH₂CH₂NH₂, hasalso been isolated, and the "hybrid" tetramine {3,5-(2,4,6-t-Bu₃C₆H₂)₂C₆H₃NHCH₂CH₂}₂NCH₂CH₂NH(4-t-BuC₆H₄) has been prepared from it. Monochloride complexes, [(TerNCH₂CH₂)₃N]MoCl, have been prepared,as well as a selection of intermediates that would be expected in a catalytic dinitrogen reduction such as[(TerNCH₂CH₂)₃N]Momages/entities/tbd1.gif">N and {[(TerNCH₂CH₂)₃N]Mo(NH₃)}{BAr'₄} (Ter = HTBT, HMT, or pBrHIPT andAr' = 3,5-(CF₃)₂C₆H₃)). Intermediates that contain the new terphenyl-substituted ligands are then evaluatedfor their efficiency for the catalytic reduction of dinitrogen under conditions where analogous [HIPTN₃N]Mospecies give four turnovers to ammonia under "standard" conditions with an efficiency of ~65%. Only[pBrHIPTN₃N]Mo compounds are efficient catalysts for dinitrogen reduction. The reasons are exploredand discussed.