反应条件
1: p-toluenesulfonic acid / CH2Cl2 / 1.5 h 2: 1.) DMSO; 2.) oxalyl chloride, triethylamine / 1.) CH2Cl2, -50 deg C, 5 min; 2.) CH2Cl2, -50 deg C 20 min, rt 3: potassium t-butoxide / 1.) THF-HMPA, -60 deg C, 30 min; 2.) -20 deg C 5 min, rt overnight 4: 95 percent / p-toluenesulfonic acid / methanol / 2 h / Ambient temperature 5: hydrogen / Pt-C / ethyl acetate 6: 1.) DMSO; 2.) oxalyl chloride, triethylamine / 1.) CH2Cl2, -78 deg C, 5 min; 2.) CH2Cl, -78 deg C 5 min, rt 7: 1.) n-butyllithium / 1.) THF-hexane, 0 deg C 30 min; 2.) THF-hexane, -30 deg C 40 min, rt 8: 97 percent / NaOH / dimethylsulfoxide / 24 h / Heating 9: 67 percent / NaH, ethanethiol / dimethylformamide / 1.) 0 deg C, 30 min rt; 2.) reflux 3 h View Scheme
参考文献
Yamagiwa, Yoshiro; Ohashi, Kinji; Sakamoto, Yoshitaka; Hirakawa, Shinji; Kamikawa, Tadao; Kubo, Isao
Tetrahedron, 1987 , vol. 43, # 15 p. 3387 - 3394
