Iron and cobalt isocyanides, Fe(CNR) 5 (1) and Co 2 (CNR) 8 (2), where R = t-butyl ( t Bu), adamantyl (Ad), and mesityl (Mes), were prepared by reduction of FeBr 2 or CoI 2 in the presence of CNR by C 8 K or silica-Na. These complexes were subjected to catalytic hydrosilylation of alkenes with hydrosiloxanes, and the results are compared with those obtained by previously reported Fe(OPiv) 2 /CNAd or Co-(OPiv) 2 /CNAd catalyst systems. Hydrosilylation of allylic ethers with 1,1,1,3,3-pentamethyldisiloxane (PMDS) catalyzed by 1 and the reaction of several alkenes with PMDS or 1,1,1,3,5,5,5-heptamethyltrisiloxane (MD′M) catalyzed by 2 exhibited greater catalytic activity than that observed for the Fe(OPiv) 2 or Co(OPiv) 2 /CNR catalyst system. Complexes 1 and 2 were effective for catalytic chemical modification of silicone fluids containing Si−H groups and for two-component silicone curing. In all cases, selectivity of the reaction in terms of formation of the desired product by hydrosilylation and of byproducts due to dehydrogenative silylation did not differ between the metal isocyanide complexes and the corresponding M(OPiv) 2 /CNR catalyst system. Catalytically active species generated from 1, 2, and the M(OPiv) 2 /CNR catalyst system were also investigated.

Reduction of nitriles to silylated primary amines was achieved by combination of 1,1,3,3-tetramethyldisiloxane (TMDS) as the hydrosilane and a catalytic amount of Co­(OPiv)2 (Piv = CO t Bu) associated with isocyanide ligands. The resulting silylated amines were subjected to acid hydrolysis or treatment with acid chlorides to give the corresponding primary amines or imides in good yields. One-pot synthesis of primary amides to primary amines with hydrosilanes was also achieved by iron–cobalt dual catalyst systems.

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Pd-catalyzed iminothiolation of alkynes took place to afford 4-SR substituted 1-azadienes regioselectively.

The novel utility of the ligand exchange reaction between M−X and RC(O)X′ (X, X′ = halogen; R = aryl, alkyl) is described. The relative ΔGs (ΔΔGs) of the oxidative additions of acid halides RC(O)X to M(PPh 3 ) 2 L n (M = Pt, Pd) were determined using the halogen-exchange reactions between X of trans-M(X)[C-(O)R](PPh 3 ) 2 and X′ of RC(O)X′. Experimental thermodynamics data are reasonably consistent with those obtained by density functional theory (DFT) calculations. Activation parameters obtained by experiments as well as a systematic DFT study supported the fact that reactions occurred through slightly distorted quadrangular pentacoordinated σ-bond metatheses, in which the Cl atom underwent a more indirect course than the Br atom. Moreover, exchange reactions were employed as the accessible prototype for the conversion of halogen ligands of nickel triad complexes into heavier halogen ligands.