Selective deoxygenation of carbonyl groups at room temperature and atmospheric hydrogen pressure over nitrogen-doped carbon supported Pd catalyst

Abstract

In this study, we have reported that a new catalyst of Pd nanoparticles supported on nitrogen-doped, highly porous carbon (Pd/NC-BT) could promote quantitative deoxygenation of carbonyl groups in a wide variety of aromatic compounds to give the fully saturated side-chain. The catalyst is unique in that it works under mild conditions at room temperature and standard hydrogen pressures. Examination of the catalytic process indicates that the presence of nitrogen atoms at the support surface and the highly porous catalyst structure are key factors contributing to the excellent catalytic performance. The nitrogen atoms act as Lewis bases sites to promote the heterolytic cleavage of H2 in coordination with the Pd nanoparticles and the porous structure facilitates the mass transfer of the substrates to the catalytic sites. Hence, the catalyst exhibits sufficient power to reduce the alcohol groups of the intermediates to give alkyl groups under mild conditions while other functional groups in the substrate molecules remain unaffected. Furthermore, the Pd/NC-BT catalyst can be recycled without observable decrease in its activity (over at least after six cycles).