Synthesis of 2-Ethylhexanal from Propylene in a Single Pot Using an Ecofriendly Multifunctional Catalyst Synthesized by Intercalation of HRhCO(TPPTS)3 Complex in the Interlayer Space of Hydrotalcite

Catalytic activity of HRhCO(TPPTS)3 intercalated hydrotalcite (Mg/Al molar ratio =3.5) as a multifunctional catalyst [HT(3.5)-INT] was studied for synthesis of C8 aldehydes (2-ethylhex-2-enal and 2-ethylhexanal) from propylene in a single pot. The effect of catalyst amount, partial pressure of propylene, and aldol temperature (T2) on the selectivity of 2-ethylhexanal and 2-ethylhex-2-enal was studied in detail to optimize the reaction parameters. The highest selectivity for C8 aldehydes (49%) was obtained at 1200 mg of catalyst and 10 atm partial pressure of propylene. Reusability experiments revealed that the HRhCO(TPPTS)3 intercalated hydrotalcite shows activity even after fourth cycle for hydroformylation reaction; however, selectivity of C8 aldehydes decreased after the second cycle. Rates of the product formation were determined individually for hydroformylation of propylene, aldol condensation of n-butanal, and hydrogenation of 2-ethylhex-2-enal catalyzed by [HT(3.5)-INT] using propylene, n-butanal,...