Journal of Industrial and Engineering Chemistry, Vol.112, 218-232, August, 2022
Highly regioselective tandem hydroformylation of substituted styrene using Iminophosphine rhodium complex immobilized on carbon
With an exponential increase in fossil fuel consumption and an increasing demand for carbon-based materials, it draws the attention of researchers to seek alternative carbon sources. Herein, we report the sustainable route for the synthesis of ionic carbon from bio-derived sugarcane-waste (Bagasse) and further anchoring with iminophosphine rhodium complex (Rh@BCNP) and utilized for tandem hydroformylation reaction. The SEM analysis confirms the formation of spherical shape morphology of carbon with sizes ranging from 30-150 nm. The successful functionalization of the iminophosphine rhodium complex on the carbon surface was determined by XPS, TEM, FE-SEM, 31P NMR, 13C CP-MAS-NMR, and FTIR analysis. Furthermore, ICP-OES analysis confirms the presence of 0.307 mmoles/g of Rh and 0.484 mmoles/g of P on the carbon surface. Rh@BCNP catalyst is the best combination of triphenylphosphine ligand, imine, and rhodium metal, resulting in hybrid material with some acidic properties of carbon that favour the selectivity towards linear products. Rh@BCNP showed remarkable catalytic performance under moderate reaction conditions (80 ℃, 40 bar (CO + H2)) in 5 h. This sharp divergence from other methods leading to linear amines and acetals results in a novel atom economic approach to synthesize pharmaceuticals and industrial products. The Rh@BCNP catalyst gave recyclability up to five cycles.
Keywords:Sugarcane waste;Carbonization;Rhodium on Carbon;Hydroaminomethylation;Hydroformylation-acetalization;Amines and acetals