toluene-4-sulfonic acid in methanol 4 h; Ambient temperature;
参考文献
Vig, O. P.; Sharma, M. L.; Kumari, Sarla; Rani, Veena
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1985 , vol. 24, p. 771 - 772
Majumdar, K. C.; Ranganayakulu, K.; Brown, R. K.
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1984 , vol. 23, # 4 p. 303 - 306