The Application Of N,p-containing Ligand In Hydrogenation Of Carbon-oxygen Double Bond

The reduction of carbon-oxygen double bond is one of the most important reactions,which has a wide range of applications.The asymmetric reduction of prochiral aromatic ketones could produce chiral aromatic alcohols,which are important pharmaceutical intermediates.The hydrogenation of carbon dioxide could produce formate and its derivatives,which is meaningful for the effective use of carbon resources and protecting the environment.At present,most catalysts applied in these reactions are noble metal catalysts,which are expensive and toxic.With the improvement of people's environmental awareness,the development of efficient,green and environment-friendly catalytic system becomes a hot issue.In this dissertation,we studied the application of the tetradentate P,N-containing ligand and various metal complexes to catalyze the asymmetric hydrogenation of aromatic ketones and the hydrogenation of carbon dioxide.We synthesize novel cobalt complexes from the inexpensive cobalt chloride,and characterized the structure.We firstly applied cobalt complexes in asymmetric hydrogenation of aromatic ketones using hydrogen as hydrogen source.The excellent chiral efficiency was obtained.Furthermore,we applied the P,N-containing ligand with various ruthenium,iridium and iron complexes in the hydrogenation of carbon dioxide.Using water as the solvent,the hydrogenation of carbon dioxide could proceed smoothly affording formate as the product.This dissertation consists of parts as follows:1.Chiral cobalt complex(R,R)-PNNO(P)-CoCl2 was applied to asymmetric hydrogenation of various aromatic ketones.Asymmetric hydrogenation of various aromatic ketones with(R,R)-PNNO(P)-CoCl2 gave the corresponding optically secondary alcohols in high yields and excellent ees(up to 95%ee)by using H2 as hydrogen source.2.Using catalytic system generated in situ from P,N-containing ligand C6P2(NH)2 and iridium complexes,we studied the hydrogenation of CO2.It showed that with the optimized reaction conditions,the C6P2(NH)2/IrCl(CO)(PPh3)2 could catalyze the hydrogenation of CO2 smoothly,affording formate as the product with TON up to 15905.