Olah, George A.; Toeroek, Bela; Joschek, Jens P.; Bucsi, Imre; Esteves, Pierre M.; Rasul, Golam; Prakash, G. K. Surya
Journal of the American Chemical Society, 2002 , vol. 124, # 38 p. 11379 - 11391
1: With methyl iodide in dimethyl sulfoxide T=20°C; 2: With potassium hydroxide in water 8 h; Heating / reflux; 3: With hydrogenchloride in water pH=1 - 2;