Synthesis of Biaryls and Teraryls

The same rhodium(I) complex could catalyze the atrop-selective completely inter-molecular [2 + 2 + 2] cycloaddition. Electron-rich internal alkynes 38, possessing the ortho-substituted phenyl group at the alkyne terminus, reacted with two molecules of 

The reaction of 2-methoxynaphthalene-derived 1,6-diyne 43 with alkynyl ester 44 in the presence of a cationic rhodium(I)/Segphos catalyst proceeded with perfect regioselectivity to give axially chiral 1,3-teraryl 45 in good yield and ee value 

The enantioselective double [2-f 2-1-2] cycloaddition reactions of 1,3-diynes with two molecules of 1,6-diynes were also developed. The enantioselective double [2+ 2-I-2] cycloaddition of electron-rich 1,3-diynes 53 with two molecules of 

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