pyridine hydrogenfluoride; 1,3-dibromo-5,5-dimethyl-hydantoin in dichloromethane T=0°C; 2 h; Argon, moisture content not more 1 volppmHF-Pyridine is about 40 times thant of the intermediate 1Intermediate 1 was introduceed into several portions;

pyridine hydrogenfluoride; 1,3-dibromo-5,5-dimethyl-hydantoin in dichloromethane As in EXAMPLE 1;

TBBDA in acetonitrile T=20°C; 0.0833333 h; chemoselective reaction;

toluene-4-sulfonic acid in toluene T=110°C; 3 h; white solid precipitation;

NiCl2((PPh3)P)2 in diethyl ether; benzene 16 h; Heating;

pyridine hydrogenfluoride; 1,3-dibromo-5,5-dimethyl-hydantoin in dichloromethane As in EXAMPLE 1;