DFT Studies Of The Selective C-O Hydrogenolysis And Ring-opening Of Biomass-derived

Tetrahydrofurfuryl alcohol(THFA)has been identified as a platform chemical of interest because of its production from biomass.It can be converted into valuable alcohols and ethers by selective hydrogenation/hydrogenolysis reaction over Rh-based metal catalysts.To better understand the chemistry of THFA,the reaction energies and the corresponding energy barriers of selective C-O bond hydrogenolysis and ring-opening of THFA on Rh(111)for the formation of 2-methyltetrahydrofuran(2-MeTHF),1,5-pentanediol(1,5-PeD),and 1,2-pentanediol(1,2-PeD)were studied using density functional theory(DFT)calculations.The results indicate that starting from THFA to produce 2-MeTHF,the direct C-O bond cleavage of the-CH2 OH group is not favored.Alternatively and more preferably,the reaction occurs through the initial activation of C?-H or O-H bond on the side chain,followed by C-O scission.On the other hand,the hydrogenolysis of THFA to give 1,5-PeD and 1,2-PeD takes place via metal catalyzed ring opening process.The activation of the C-O bond appears to proceed via the sequential scission of vicinal C-H bonds in the five-membered ring followed by the dissociation of the C-O bond.The hydrogenolysis predominantly proceeds at the C-O bond comprised of secondary oxygen atoms thus resulting in the formation of 1,2-PeD.Furthermore,the intermediates during THFA hydrogenolysis reaction to 1,5-PeD and 1,2-PeD are thermodynamically favored than those to 2-MeTHF.Our findings are consistent with the experiments,in which 1,5-PeD and 1,2-PeD are the major products of THFA hydrogenolysis,with trace of 2-MeTHF formed.In addition,we are also add dressing agent on Rh,on which the hydrogenolysis of THFA is analyzed.We study the formation of diol in DFT,because the main product grown on the catalyst is diol.Research results show that the metal oxides reacts with H2 in gas phase to form bifunctional metal.This make the force stronger between THFA and metal surface,furthermore,the C-O bond breaks easier to produce diol.