1: With dichloroborane*dioxane in dichloromethane 4 h; Heating; 2: With water cooling;

water in diethyl ether; dichloromethane under N2; to excess of H2O in Et2O added cooled (0 °C) soln. of B complex in CH2Cl2 with stirring, stirred for 10 min; water layer sepd., org. layer washed with cold H2O and brine, dried with MgSO4, evapd. in vac., recrystd. from C6H6;

sodium periodate; ammonium acetate; water in acetone T=25°C;

tetrakis(triphenylphosphine) palladium(0); caesium carbonate in ethanol T=70°C; 2 h;