Steric effects in organometallic compounds. A Rh-103 NMR study of alkylrhodoximes

被引：28

作者：

Asaro, F

Costa, G

Dreos, R

Pellizer, G

vonPhilipsborn, W

机构：

[1] UNIV TRIESTE,DIPARTIMENTO SCI CHIM,I-34127 TRIESTE,ITALY

[2] UNIV ZURICH,INST ORGAN CHEM,CH-8057 ZURICH,SWITZERLAND

来源：

JOURNAL OF ORGANOMETALLIC CHEMISTRY | 1996年 / 513卷 / 1-2期

关键词：

Rh; alkylrhodoximes; Rh-103; NMR; steric effects; chemical shifts;

D O I：

10.1016/0022-328X(95)06052-X

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Three series of alkylrhodoximes [Rh(Hdmg)(2)RL] (Hdmg = monoanion of dimethlyglyoxime) (L = H2O, R = Me, Et, Pr-n, Pr-i, (n)Bu, (i)Bu, (neo)Pent; L = py, R = Me, Et, Pr-n, Pr-i, (n)Bu, (i)Bu, (s)Bu, (t)Bu, (neo)Pent, adam, CH2Cl, CH2CF3; L = PPh(3), R = Me, Et, Pr-n, Pr-i, (n)Bu, (i)Bu, (t)Bu, (neo)Pent, adam) were prepared and characterized by H-1, C-13 acid P-31 NMR spectra; several of the reported compounds are new. The rhodium-103 chemical shifts were measured by (H-1, Rh-103)-2D inverse correlation for the complexes with L = H2O and py and by (P-31, Rh-103)-{H-1}-2D inverse correlation for those with L = PPh(3). Rh shielding decreases in the order Et > Me > (n)Bu > Pr-i > (s)Bu > (neo)Pent > (t)Bu. Discussion of the shift dependence on the various alkyl parameters allows us to conclude that, in these compounds the R ligand affects rhodium shielding mainly through distortions of the coordination site due to its bulk, The (1)J[Rh,P] values reflect the rhodium-phosphine binding interaction.

引用

页码：193 / 200

页数：8

共 36 条

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