Enantioselective hydroamination/cyclization of N-aryl alkynylarylpropynamides such as I (R = H, Ph, 2-MeOC6H4) in the presence of AuCl(SMe2), silver triflate, and (R)- or (S)-BINAP yielded nonracemic azahelicenes such as (-)-II (R = Ph, 2-MeOC6H4) or (+)-II (R = H) in 44-97% yields and in 30-74% ee; the use of excess silver triflate in combination with a gold catalyst was necessary for the reaction. The S-shaped double azahelicene III (R1 = 2-MeOC6H4) was prepd. using the enantioselective hydroamination/cyclization of a naphthalenylbis(arylethynylnaphthylpropynamide) as the key step. The optical rotations and UV, fluorescence, and circularly polarized luminescence spectra of two azahexahelicenes, III, and its dilactam precursor were obtained; the circularly polarized luminescence (CPL) activity of the S-shaped double azahelicenes was significantly higher than that of the azahelicenes. [on SciFinder(R)]
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