1: With potassium carbonate in water T=40°C; 6 h; Inert atmosphere; 2: With 2,4,6-trichloro-1,3,5-triazine in dichloromethane; water; N,N-dimethyl-formamide T=0°C; Inert atmosphere; 3: With sodium hydroxide in dichloromethane; water pH=11; Inert atmosphere;