STABLE ORGANOPLATINUM(IV) COMPLEXES WITH PENDANT FREE-RADICALS

被引：15

作者：

RENDINA, LM

VITTAL, JJ

PUDDEPHATT, RJ

机构：

[1] Department of Chemistry, The University of Western Ontario, London

来源：

ORGANOMETALLICS | 1995年 / 14卷 / 05期

关键词：

D O I：

10.1021/om00005a019

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Oxidative addition of 2-bromoacetamido derivatives of the stable, free-radical nitroxides tempo and proxyl (2,2,6,6-tetramethylpiperidinyl-N-oxyl and 2,2,5,5-tetramethylpyrrolidinyl-N-oxyl, respectively) to [PtMe(2)(bpy)] (bpy = 2,2(')-bipyridine) affords the novel organoplatinum-(IV) complexes [Pt{CH2C(O)NH-tempo}BrMe(2)(bpy)] (1), [Pt{CH2C(O)NH-proxyl}BrMe(2)(bpy)] (2), [Pt{CH2C(O)NHCH2-proxyl}BrMe(2)(bpy)] (3), [Pt{CH2C(O)NHCH2C(O)NH-proxyl}-BrMe(2)(bpy)] (4), and [Pt{CH2C(O)NH(CH2)(3) NHC(O)-proxyl}BrMe(2)(bpy)] (5) in good yields. The complexes exist as a mixture of trans (a) and cis (b) isomers and are the result of traits and cis oxidative addition, respectively. The broad H-1 NMR spectra and distinctive three-line pattern in the ESR spectra conclusively demonstrate the paramagnetic nature of the complexes. The X-ray structure of la was determined. Crystals of la are monoclinic, space group P2(1)/c, with a = 13.401(2) Angstrom, b = 16.979(1) Angstrom, c = 11.199(1) Angstrom, beta = 93.01(1)degrees, Z = 4, and R = 0.0499. The bromo and Pt-C sigma-bonded 4-(2-acetamido)-tempo ligands occupy a mutually trans arrangement about the octahedral platinum(IV) center. Complexes 1-5 are rare examples of stable organometallic species with pendant free radicals.

引用

页码：2188 / 2193

页数：6

共 18 条

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