Design And Synthesis Of Two Kinds Of Novel Chiral Bifunctional Organocatalysts With Hydrogen Bonds Donors And Their Application In The Asymmetric Catalysis

Cinchona alkaloid skeleton is quite attractive in the field of asymmetric catalysis due to its multiple chiral centers,rigid conformation,the characteristics of the special electronic and the molecular structure complexity.It has been widely used as the �privilege� skeleton in the asymmetric catalysis area.Based on the cinchona alkaloids,we constructed two kinds of catalysts,including thiourea and guanidine,which were used in the asymmetric reactions to compare the classical taddol derived guanidine catalysts for the catalytic reaction effects.The results show that the cinchona derivatives of the chiral catalysts have good catalytic performance in the asymmetric Michacel addition.The main contents of this thesis included the following four parts:1.24 novel catalysts were synthesized from different cinchona alkaloids,including 12 chiral thiourea catalysts,2 urea catalysts and 10 chiral guanidine catalysts.And 4 novel catalysts were synthesized from tartaric acid,including a thiourea and 3 chiral guanidine.Structures of these chiral catalysts were confirmed by IR?1H NMR?13C NMR?LC-MS and HRMS.2.The chiral thiourea catalysts were applied in the asymmetric Michael addition reaction of dithiomalonates to trans-?-nitroolefins.The products were obtained with high yields(up to 95%)and excellent enantioselectivities(up to 99%)under mild conditions while using 40 i.On the basis of experiments,and a transition state was proposed in the thiourea catalytic asymmetric Michael addition reaction to explain the chiral induction process.3.A series of chiral guanidine catalysts were also applied into the asymmetric Michael addition reaction.These reactions can be carried out smoothly at room temperature.High yields(up to 92%)and excellent enantioselectivities(up to 99%)of the Michael addition reaction products were obtained by screening the catalysts and optimizing the reaction conditions.4.The chiral catalysts were applied in the asymmetric Henry reaction,though screening the conditions to obtain the moderate yield(up to 45%)and good enantioselectivity(up to 81%).These results showed that the asymmetric Michael addition reaction were efficient,which highly selectively were catalyzed by the cinchona alkaloid derived chiral guanidine and chiral thiourea catalysts.Among these catalysts,chiral thiourea catalysts have shown the best performance result.This methodology provided an efficient and practical method for obtaining high enantioselectivity ?-amino acid derivatives own to its high selectivity,mild conditions,low cost and good compatibility for obtaining a wide range of useful substrates.And the cinchona alkaloids derived catalysts can also be potentially applied into other asymmetric reactions.