82489-53-0

Upstream product

• 82489-51-8 Fe(CO)4(CNCH₂C₆H₅) 
• 88333-03-3 Benzyl isocyanide 
• 82489-51-8 [Fe(CO)4(CNCH₂C₆H₅)] 

Downstream Products

• 82489-67-6 Fe(CO)2(CNCH₂C₆H₅)2(C₂(CN)4) 

Relevant academic research and scientific papers

DI- AND POLY-NUCLEAR TRANSITION METAL COMPLEXES AS CATALYSTS FOR THE METAL CARBONYL SUBSTITUTION REACTION. THE ROLE OF SUPPORTED METALS AND METAL OXIDES AS CATALYST PROMOTERS

Various di- and poly-nuclear transition metal complexes have been investigated as catalysts for the metal carbonyl substitution reaction.The complexes 5-C5H4R)Fe(CO)2>2> (R=H, Me, CO2Me, OMe, O(CH2)4OH) and 5-C5H5)Ru(CO)2>2> are active catalysts for a range of substitution reactions including the probe reaction t)>+ButNC->t)2>+CO. 5-C5Me5)Fe(CO)2>2> is catalytically active only on irradiation with visible light.For 5-C5H5)Fe(CO)2>2> and a range of isocyanides RNC (R=But, C6H5CH2, 2,6-Me2C6H3), catalyst modification by substitution with isocyanide is a major factor influencing the degree of the catalytic effects observed, e.g. 5-C5H5)Fe(CO)(CNBut)>2> is approximately 35 times as active as 5-C5H5)2Fe2(CO)3(CNBut)> for the t)>->t)2> conversion.Mechanistic studies on this system suggest that the catalytic substitution step probably involves a rapid intermolecular attack of isonitrile, possibly on a labile catalyst-substrate radical intermediate such as 5-C5H5)Fe(CO)2>>*, or on a reactive radical cation such as + generated via electron transfer between the substrate and the catalyst.Other transition metal complexes which also catalyze the substitution of CO by isocyanide in (and (M=Cr, Mo, W), , ) include , , (M=Co, Ir) and .These reactions conform to the general mechanistic patterns established for 5-C5H5)Fe(CO)2>2>, suggesting a similar mechanism.A range of materials, notably PtO2, PdO and Pd/C, act as promoters for the homogeneous di- and poly-nuclear transition metal catalysts, and can even be used to induce activity in normally inactive dimer and cluster complexes e.g. .This promotion is attributed to at least three possible effects: the removal of catalyst inhibitors, a catalyzed substitution of the homogeneous catalyst partner, and a possible homogeneous-heterogeneous interaction which promotes the formation of catalytic intermediates.

SUPPORTED TRANSITION METALS AND METAL OXIDES AS CATALYSTS FOR THE METAL CARBONYL SUBSTITUTION REACTION

A range of supported transition metals and metal oxides have been investigated as catalysts for the metal carbonyl substitution reaction M-CO+L->M-L+CO (L=isocyanide (RNC), Group V donor ligand).The use of model substitution reactions reveals the metals Pd, Pt, Ru and Rh and the oxides PdO and PtO2 to be efficient catalysts for substitution reactions of mono-, di- and polynuclear metal carbonyl complexes, and, while there are observable effects which relate to the nature of the catalyst support, catalyst dispersion, catalyst activation and catalyst poisoning, the generally observed orders of activity are Pd>Pt>Ru>Rh and PdO>PtO2.The radical traps hydroquinone and galvinoxyl have an inhibiting effect on catalyst, while light has a mild promotional effect.These observations are consistent with a catalytic mechanism similar to that observed for 5-C5H5)Fe(CO)2>2>, namely a radical non-chain process.The metal and metal oxides display considerable potential for the synthesis of substituted metal carbonyl complexes including 5-n(CNR)n> (n=1-5), 6-n(CNR)n> (M=Cr, Mo, W; n=1-3), (M3(C)12-n(CNR)n> (M=Ru,(n=1-3; M=Os, n=1-4), and (L=Group V donor ligand).Certain catalyst supports (zeolites, activated carbon) have themselves been found to possess mild activity for the catalytic carbonyl substitution reaction.

Catalysed and Non-catalysed Reaction Between and Isonitriles

The reaction between and isonitrile, RNC, is catalysed by CoCl2*H2O and readily yields the complexes (n = 1-3, R = Me, C6H11, tBu, PhCH2, Ph, 2,6-Me2C6H3, or 2,4,6-Me3C6H2; n = 4, R = tBu; n = 4 or 5, R = Ph, 2,6-Me2C6H3, or 2,4,6-Me3C6H2).The high-yield synthesis of from and RNC in the absence of catalyst is also reported.Trimethylamine N-oxide has been used to synthesize from and RCN and results are compared with the CoCl2 catalysed reaction.All products were characterized by i.r. and n.m.r. spectroscopy.The higher substituted derivatives were further characterized by reaction with I2 and tetracyanoethylene (tcne) and gave (n = 2, R = tBu, PhCH2, or 2,6-Me2C6H3; n = 3, R = tBu or 2,6-Me2C6H3; n = 4, R = 2,6-Me2C6H3) and cis- and trans- from appropriate starting materials.Mechanistic data suggest that the reaction occurs via attack of catalyst at a co-ordinated CO ligand.Subsequent attack by unco-ordinated RNC in an intermolecular, non-bridging mechanism leads to the required isonitrile derivatives.