Synthesis,Structure And Physicochemical Properties Of Tetrazolium Energetic Complexes

This paper is concerned with the studies on introducing the concept of Dynamic Kinetic Asymmetric Transformation in the reactions, utilizing the chiral Pd-N-heterocyclic carbene (Pd-NHC) complexes as the catalysts, successfully achieved the transformation of the racemic biaryls to the spirocyclic products bearing an all-carbon quaternary stereocenter in good yields with excellent enantioselectivities. A mild condition, efficient synthesis method has been developed.It consists the following two parts:Chapter I:This chapter summarizes the concept of the asymmetric synthesis, mainly using asymmetric resolution and transformation to establish the chiral compounds, for this concept including the following parts:(1) kinetic resolution; (2) parallel kinetic resolution; (3) dynamic kinetic resolution; (4) dynamic kinetic asymmetric transformation. Traditional asymmetric synthesis is that introducing the chiral auxiliaries to transfer the symmetry strating materials to the chiral molecules in the reactions, usually needs to consume the stoichiometric chiral auxiliaries, but in the asymmetric catalytic synthesis only needs a catalytic amount of the chiral metal complexes or enzyme to control the enantiotopic faces of reactants, and then we will obtain the chiral products. This method is a more economic and effective solution to synthesize a large number of chiral compounds. This chapter mainly introduce the catalytic asymmetric synthesis reactions.Chapter II:Great advances have been achieved in dynamic kinetic asymmetric transformation of synthetic of the enantiopure compound in the field of asymmetric synthesis. However, DYKAT of the racemic biaryls, with concomitant creation of a new sp3 stereocenter remains a daunting challenge. This process, to the best of our knowledge, is the first successful example of transferring one class of racemic atropisomeric biaryls into another type of optically enriched compounds with central chirality relying on the DYKAT strategy. The features of this reaction are mild conditions, convenient operation, the materials easy to get and have good yields with excellent enantioselectivities.