1. Research Of Pd/norbornene Catalyzed Asymmetric Aryl-aryl Coupling Reaction 2. Design, Synthesis And Application Of Novel Oxazoline Ferrocene Ligands In Asymmetric Reactions

Biaryl axis is the core structure of many compounds. Many efforts have been put into the synthesis of biaryl compounds. Direct C–H activation of Csp2 and Csp3 bonds has opened a variety of synthetic pathways involving C–C bond formation. The research of asymmetric coupling reaction of aromatic compounds not only has important application value, but also has enlightening significance for other reaction routes.This thesis takes working out new synthetic methods, designing and preparing novel biaryl compounds and chiral ligands, and investigating the reaction mechanism as the starting point. With new synthetic methods, a series of biphenyl derivatives were synthesized. The synthesis of biphenyl compounds containing chiral structure catalyzed by organocatalysis was also studied. In addition, in this thesis, novel ferrocene ligands containing ionic fragments were designed and prepared. The ligands were applied in the asymmetric hydrogenation of aryl ketones catalyzed by ruthenium. The catalytic performance was also studied.The main contents of this thesis are as follows.1. Competitive pathways in Pd-catalyzed synthesis of arylphenolsNovel developments are described, which have been achieved in the framework of the studies of sequential palladium-catalyzed reactions, involving palladacycle formation with norbornene or norbornadiene via aromatic C–H activation. The use of o-bromophenols as partners of iodobenzenes has led to ring formation after norbornene deinsertion, or to arylphenols, containing a pendant norbornenyl or norbornadienyl group or to vinylarylphenols. The availability of a reductive elimination step drives the reaction course towards a preferential product. The mechanism was analyzed.2. The study of a sequential Pd/norbornene-catalyzed process generating o-Biaryl carbaldehydes or ketones in the presence of a third basic catalyst or 6H-dibenzopyrans by C–O ring closureThis thesis reports the synthesis of o-biaryl carbaldehydes and ketones or dibenzopyran derivatives. Aldehydes and ketones were obtained through the one-pot reaction of o-aryl iodides with o-bromobenzyl alcohols under the triple catalytic action of Pd, norbornene, and a base. Dibenzopyrans result from Pd and norbornene catalysis with a different termination, leading to C–O ring closure. In both cases the process first leads to a 5-membered palladacycle, which controls C–C coupling, then to a 7-membered oxapalladacycle, which gives aldehydes and ketones or dibenzopyrans. This is a new one-pot method, in most cases with good to excellent(yield = 99%) selectivity.3. A novel enantioselective synthesis of 6H-dibenzopyran derivatives by Pd/norbornene/ cinchona alkaloids combined catalysisThe chiral synthesis of dibenzopyran skeletons is an important issue for therapeutic modification. To obtain chiral substituted dibenzopyran derivatives, organocatalysts were used. Previously, 6H-dibenzopyran derivatives were synthesized though a one-pot procedure with satisfactory yields. Herein, this thesis describes a novel synthesis of chiral dibenzopyran by a one-pot tandem reaction catalyzed bypalladium, norbornene, and a cinchona alkaloid base, with good yields and satisfactory enantioselectivities.4. Design, synthesis and application of novel ferrocene ligands containing ionic fragments in asymmetric hydrogenation reactionsSeveral kinds of planar chiral ferrocene quaternary ammonium salt ligands were designed and synthesized. They were applied in the asymmetric hydrogenation for a series of aryl ketones. The single crystal X-ray structure of the ligand further confirmed the structure and has reference value for the study of the properties of the ligand.N, P of the ligand coordinate with Ru, and H2 was induced with chirality to the C=O double bond of the substrates. The catalysis has high catalytic activity. Therefore, aryl alcohols were obtained with satisfactory yields and high enantioselectivities(up to 99.7%). The molar ratio of substrate and catalyst could reach 104. Compared with the catalyst without ionic fragment, this kind of catalysts can give better results within a short period of reaction time. The separation and recovery of the catalyst is convenient. During the recovery steps, the enantioselectivity maintains.5. Enantioselective Synthesis of New Dimeric Chromene Derivatives by Ferrocene-Copper Catalyst SystemNew 2-iminochromene dimers were successfully prepared under mild condition. In addition, siloxane-substituted siloxane-substituted ferrocenyloxazolinephosphine(FOXAP) ligand was successfully applied in the enantioselective self-Michael reactions of 2-iminochromene with satisfactory yields and excellent ee values.