boron tribromide in dichloromethane T=0°C; 0.5 h;

1: 1.) Mg / 1.) THF, 2.) THF, r.t., 2 h 2: 96 percent / hydroxylamine hydrochloride, pyridine / ethanol / 12 h / 60 °C 3: Et3N, (N,N-dimethylamino)pyridine / CH2Cl2 / 0.75 h / Ambient temperature 4: liq. NH3 / CH2Cl2 / 18 h / Ambient temperature 5: 77 percent / tert-butyl hypochlorite, Et3N / ethanol; 2-methyl-propan-2-ol / 2 h / Ambient temperature 6: 1.) thallium(III) trifluoroacetate, 2.) PdCl2, LiCl, MgO / 1.) TFA, r.t., 24 h, 2.) r.t., 43 h 7: 98 percent / BBr3 / CH2Cl2 / 0.5 h / 0 °C View Scheme

1: 96 percent / hydroxylamine hydrochloride, pyridine / ethanol / 12 h / 60 °C 2: Et3N, (N,N-dimethylamino)pyridine / CH2Cl2 / 0.75 h / Ambient temperature 3: liq. NH3 / CH2Cl2 / 18 h / Ambient temperature 4: 77 percent / tert-butyl hypochlorite, Et3N / ethanol; 2-methyl-propan-2-ol / 2 h / Ambient temperature 5: 1.) thallium(III) trifluoroacetate, 2.) PdCl2, LiCl, MgO / 1.) TFA, r.t., 24 h, 2.) r.t., 43 h 6: 98 percent / BBr3 / CH2Cl2 / 0.5 h / 0 °C View Scheme

1: Et3N, (N,N-dimethylamino)pyridine / CH2Cl2 / 0.75 h / Ambient temperature 2: liq. NH3 / CH2Cl2 / 18 h / Ambient temperature 3: 77 percent / tert-butyl hypochlorite, Et3N / ethanol; 2-methyl-propan-2-ol / 2 h / Ambient temperature 4: 1.) thallium(III) trifluoroacetate, 2.) PdCl2, LiCl, MgO / 1.) TFA, r.t., 24 h, 2.) r.t., 43 h 5: 98 percent / BBr3 / CH2Cl2 / 0.5 h / 0 °C View Scheme

1: 1.) thallium(III) trifluoroacetate, 2.) PdCl2, LiCl, MgO / 1.) TFA, r.t., 24 h, 2.) r.t., 43 h 2: 98 percent / BBr3 / CH2Cl2 / 0.5 h / 0 °C View Scheme

1: 77 percent / tert-butyl hypochlorite, Et3N / ethanol; 2-methyl-propan-2-ol / 2 h / Ambient temperature 2: 1.) thallium(III) trifluoroacetate, 2.) PdCl2, LiCl, MgO / 1.) TFA, r.t., 24 h, 2.) r.t., 43 h 3: 98 percent / BBr3 / CH2Cl2 / 0.5 h / 0 °C View Scheme

1: liq. NH3 / CH2Cl2 / 18 h / Ambient temperature 2: 77 percent / tert-butyl hypochlorite, Et3N / ethanol; 2-methyl-propan-2-ol / 2 h / Ambient temperature 3: 1.) thallium(III) trifluoroacetate, 2.) PdCl2, LiCl, MgO / 1.) TFA, r.t., 24 h, 2.) r.t., 43 h 4: 98 percent / BBr3 / CH2Cl2 / 0.5 h / 0 °C View Scheme