Reactions of the sterically encumbered m‐terphenyl isocyanides CNAr^Dipp2 (Dipp = 2,6‐diisopropylphenyl) and CNAr^Mes2 (Mes = 2,4,6‐trimethylphenyl) with (NBu₄)[ReOCl₄] in CH₂Cl₂ form stable complexes of the composition (NBu₄)[ReOCl₃(CNAr^R)] or [ReOCl₃(CNAr^R)₂] depending on the amount of isocyanide added. In the [ReOCl₃(CNAr^R)₂] complexes, cis coordination of the two isocyanides is observed for CNAr^Mes2, while the sterically more demanding CNAr^DIPP2 ligands are found in trans positions. The rhenium(III) species [ReCl₃(PPh₃)(CNAr^Mes2)₂] was obtained from the reaction of [ReOCl₃(PPh₃)₂] and CNAr^Mes2. The ν(CN) IR frequencies measured for the Re^V complexes appear at higher wavenumbers than for the uncoordinated isocyanides, which suggests a low degree of backdonation into anti‐bonding orbitals of these ligands.

中文翻译：

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氧化or（V）和R（III）与间-三苯异氰酸酯的配合物

的空间位阻的反应米三联苯异氰化物CNAR ^Dipp2（迪普= 2,6-二异丙基）和CNAR ^Mes2（MES = 2,4,6-三甲基苯基）与（NBU ₄）[ReOCl ₄ ]在CH ₂氯₂形式稳定组合物（NBu ₄）[ReOCl ₃（CNAr ^R）]或[ReOCl ₃（CNAr ^R）₂ ]的配合物取决于异氰酸酯的添加量。在[ReOCl ₃（CNAr ^R）₂ ]配合物中，观察到两个异氰酸酯的顺式配位^Mes2，而在空间上更需要CNAr ^DIPP2配体的位置是反式。由[ReOCl ₃（PPh ₃）₂ ]和CNAr ^Mes2的反应获得species（III）物质[ReCl ₃（PPh ₃）（CNAr ^Mes2）₂ ] 。Re ^V络合物测得的ν（CN）IR频率出现的波数高于未配位的异氰化物，这表明这些配体的反键化程度较低。