ASYMMETRIC CONVERSION OF (Z)-N-BENZOYL-alpha-DEHYDRO(9-PHENANTHRYL)ALANINE N '-METHYLAMIDE INTO ITS CYCLIZATION INTERMEDIATES VIA PHOTOINDUCED ELECTRON TRANSFER

作者：Matsuki Shin ichi^*; Kimura Takayuki; Hattori Shinsaku; Kawai Kaoru; Igarashi Tetsutaro; Sakurai Tadamitsu

来源：Heterocycles, 2013, 87(6): 1337-1347.

DOI：10.3987/COM-13-12724

Irradiation of (Z)-N-benzoyl-alpha-dehydro(9-phenanthryl)alanine N'-methylamide [(Z)-1] in 2-propanol-methanol (4:1 v/v) containing (S)-nicotine afforded the (3S,8aS)-3,8a-dihydrodibenzo[f,h]quinolinone derivative [(3S,8aS)-2] and (3R,8aS)-2 in 20% and 35% enantiomeric excess (ee), respectively. Analysis of the effects of a chiral amine and solvent on the electron transfer-initiated enantioselective photocyclization of (Z)-1 revealed that the magnitude of the ee is predominantly determined by the ability of this amine to form hydrogen bonds at the two sites of the enol intermediate as the precursor of 2.

• 出版日期2013-6-1