Alkene dissociation from a d0 yttrocene-alkyl-alkene complex generates a pyramidal alkyl yttrium complex that inverts slowly

被引:43
作者
Casey, CP [1 ]
Fagan, MA [1 ]
Hallenbeck, SL [1 ]
机构
[1] Univ Wisconsin, Dept Chem, Madison, WI 53706 USA
关键词
D O I
10.1021/om971008t
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The d(0) yttrium(III)-alhyl-alkene chelate Cp*Y-2[eta(1):eta(2)-CH2CH2CH(CH3)CH=CH2] (5) was prepared by reaction of 3-methyl-1,4-pentadiene with (Cp*(2)-YH)(2). VariabLe-temperature C-13 NMR spectroscopy of 5 showed that the environments of the two diastereotopic Cp* ligands were averaged by a fluxional process which requires both reversible alkene dissociation and inversion at the yttrium center; the energy barrier fur alkene dissociation pins yttrium inversion is 9.6 +/- 0.3 kcal mol(-1).
引用
收藏
页码:287 / 289
页数:3
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