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Simple and efficient diphosphinite ligands were evaluated in rhodium catalyzed hydroformylation of vinyl acetate. The effect of various reaction variables like temperature, pressure, substrate/Rh ratio, P/Rh ratio, solvents, time and different types of phosphorous ligands were studied. The diphosphinite ligand exhibited a considerable impact on the hydroformylation of vinyl esters and provided good turnover number (up to 10,000) with excellent regioselectivity (99%) to branched aldehyde. Wide range of vinyl esters including long chain aliphatic vinyl esters (up to C18) were well tolerated to provide good to excellent yield of desired product.

A simple and efficient Rh-phosphinite complex catalyst was studied for the selective hydroformylation of various olefins. The influence of various reaction parameters including the effect of temperature, pressure, catalyst loading, time, and solvents was studied. The protocol was also applied for the synthesis of various acetals via tandem hydroformylation–acetalization of olefins in alcohols as solvents. High activity and selectivity for acetal formation was achieved in the absence of co-catalysts with admirable substrate to catalyst mole ratio (TON 2500). The developed protocol works for a wide range of olefins to synthesize corresponding aldehydes and acetals under optimized reaction conditions.

Hydroaminomethylation of various olefins with primary and secondary amines was carried out using a simple and efficient rhodium–phosphinite complex catalyst. The influence of various reaction parameters including the effects of temperature, pressure, catalyst loading, time and solvents has been investigated. The present protocol is general with wider substrate applicability for the synthesis of an important class of aliphatic amines and arylethylamines. High activity and selectivity for amines was achieved with a very good substrate/catalyst molar ratio (turnover number 2500) under mild reaction conditions. Copyright © 2013 John Wiley & Sons, Ltd.

The carbonylative cyclization of o-iodobenzoic acid with a variety of primary amines and carbon monoxide (1 bar) using a polymer-supported palladium–N-heterocyclic carbene complex (PS-Pd-NHC) as the catalyst gives N-substituted 1H-isoindole-1,3(2H)-diones (phthalimides) in good to excellent yields with a short reaction time. The catalyst is efficient, heterogeneous, and phosphine-free, it exhibited remarkable activity and it is also recyclable (4 consecutive cycles). The use of methyl o-iodobenzoate as the substrate under these conditions also gave N-substituted 1H-isoindole-1,3(2H)-diones, but with lower yields. Cyclization of o-iodobenzyl alcohol with carbon monoxide under these conditions gave isobenzofuran-1(3H)-one (phthalide).

The application of palladium on carbon (Pd/C) as a heterogeneous recyclable catalyst was investigated for the double carbonylation of o-dihaloarenes with amines providing excellent yield of N-substituted phthalimides in shorter reaction time as compared to earlier reported homogeneous protocols. Furthermore, the scope of the developed protocol was applied for the synthesis N-substituted phthalimides from o-halobenzoates and o-halobenzoic acid via a single step carbonylative cyclization reaction. The developed methodology describes an efficient one-step approach for the synthesis of an important class of heterocycles and tolerates a wide variety of functional groups. It circumvents the use of phosphine ligands with an additional advantage of catalyst recyclability for up to eight consecutive cycles.

The optimized reaction conditions allow the hydroaminomethylation of olefins to produce secondary or tertiary amines.

The reaction does not require any acid co-catalysts and tolerates aromatic and aliphatic alkenes.

o-Halobenzoic acids or the corresponding methyl ester are treated with primary amines under optimized conditions.

Double carbonylation of o-diiodobenzene (I) in the presence of aromatic and aliphatic amines proceeds readily in the presence of Pd—C catalyst to afford phthalimides (IV) and (VI) in high to excellent yields.

A complete green and convenient strategy for the chemoselective transfer hydrogenation of various α,β-unsaturated carbonyl compounds using HCOONa as hydrogen source and a polymer-supported Pd-NHC catalyst system is given.

An highly efficient PS-Pd-NHC catalytic system has been developed for chemoselective conjugate reduction of α,β-unsaturated carbonyl compounds providing good to excellent conversion with remarkable chemoselectivity (up to 100%). The developed protocol is more advantageous due to use of HCOONa as hydrogen source, environmentally benign water as solvent and effective catalyst recyclability.