Intermolecular coupling reactions of inversely polarized carbene ligands starting from the Cp2*Ti=C=CH2 intermediate and chromium carbene complexes

被引：2

作者：

Beckhaus, R ^{[1
]}

Oster, J ^{[1
]}

机构：

[1] Tech Hsch Aachen, Inst Anorgan Chem, D-52056 Aachen, Germany

来源：

JOURNAL OF ORGANOMETALLIC CHEMISTRY | 1998年 / 553卷 / 1-2期

关键词：

intermolecular coupling; carbene complexes; titanium complexes; chromium complexes; vinylidine complexes;

D O I：

10.1016/S0022-328X(97)00638-4

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The titanaallene intermediate [Cp-2*Ti=C=CH2] (2), generated thermally from Cp-2*Ti(CH=CH2)CH3 (1), reacts with methoxyalkyl carbene complexes (CO)(5)Cr=C(OCH3)R (3) [R = CH3 (a), CD3 (b), Et (c)] by CC-coupling of the carbene ligands to give the heterodinuclear complexes Cp-2* <(TiCH2C(=C(OCH3)R)C(=Cr(CO)(5))O)over bar> (4) and Cp-2*<(TiCH2C(=C(mu-OCH3)R)C(=Cr(CO)(4))O)over bar> (5). An unusual isomerization of the exocyclic double bond, which occurs by thermal conversion 4c --> 5c, can be explained considering ionic resonance forms. The addition of one CO molecule to 5c leads to a displacement of the methoxy coordination. On the other hand, the aminocarbene complex (CO)(5)Cr=C((NHPr)-Pr-1)CH3 (8), which is less electrophilic than alkoxycarbenes, reacts with 2 to give a dinuclear dititanacyclobutene complex (9). Its blue-violet colour is probably caused by a twist around the single bond C(beta)-C(beta) of the dititanacyclobutene unit. (C) 1998 Elsevier Science S.A.

引用

页码：427 / 432

页数：6

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