1: With cesium fluoride in N,N-dimethyl-formamide T=80°C; 6 h; Inert atmosphereMolecular sieve; 2: With hydrogenchloride in water; N,N-dimethyl-formamide T=20°C; 0.5 h; Inert atmosphereMolecular sieve;

borane in tetrahydrofuran 24 h; Ambient temperature;