Cascade Chan-Lam Coupling Reactions Of Arylhydroxylamines With Arylboronic Acids

Carbon-hetero atom bonds are widely found in many biologically active molecules,drugs and organic functional materials,so their construction is very important in organic synthesis.The Chan-Lam coupling reaction,which refers to the Copper-mediated cross-coupling between nitrogen nucleophiles or oxygen nucleophiles and organoboron compounds,is an important method to construct carbon-heteroatom bonds(C-N bonds,C-O bonds).Compared with other transition metal-catalyzed coupling reactions,Chan-Lam coupling reaction employs the cheap copper salt as catalyst,be carried out at room temperature under air without additional ligands,and the catalytic conditions are mild with high efficiency.Therefore,Chan-Lam coupling reaction has made a lot of progress in recent years.The highly valuable biaryl structural motif is widespread present in organic functional materials,pharmaceutical molecules and catalysts.Especially axialchiral biaryl compounds,such as NOBIN,BINOL,BINAP and their analogs,are widely used as chiral ligands and auxiliaries in catalytic enantioselective transformations.Therefore,the preparation of biaryl compounds is very important in organic synthesis.This thesis developd the Chan-Lam type O-arylation/[3,3]-rearrangement/rearomatization tandem reaction of aryl hydroxylamine and aryl boronic acid to construct a series of NOBIN-type biaryl compounds.This paper consists of three parts:In the first part,we briefly introduce the recent progress of Chan-Lam coupling reaction to construct C-N bonds and C-O bonds,and the construction methods of biaryl compounds under transition-metal-catalyzed and transition-metal-free conditionsIn the second part,we developed a copper-mediated Chan-Lam type O-arylation of arylhydroxylamines with arylboronic acids to generate transient N,O-diaryl-hydroxy lam ines that could rapidly undergo cascade[3,3]-sigmatropic rearrangement and rearomatization to afford a series of NOBIN-type biaryls under mild conditions.This protocol owns readily available substrates,mild reaction conditions,and broad substrate scope.This cascade reaction expands the application of the Chan-Lam coupling reaction and provides a new method for the synthesis of NOBIN-type biaryl compounds.In the third part,we developed a protocol of chiral-DMAP-catalyzed O-acylation of biaryl compounds and isobutyric anhydride to realize the kinetic resolution of the NOBIN-type biaryls synthesized in the second part.Racemic biaryls with diverse substituents onto the aromatic ring have moderate to good resolution effect with more than 20 selectivity.