tri-n-butyltin azide in xylene 1.) 120 deg C, 60 h, 2.) 130 deg C, 4 h;

1: 1.) n-BuLi, 2.) zinc chloride, 3.) Pd(Ph3P)4 2: boron tribromide / CH2Cl2 / 1.) -78 deg C - RT, 2.) RT, overnight 3: 48 percent / tri-n-butyltin azide / xylene / 1.) 120 deg C, 60 h, 2.) 130 deg C, 4 h View Scheme

1: 1.) n-BuLi, 2.) zinc chloride, 3.) Pd(Ph3P)4 2: boron tribromide / CH2Cl2 / 1.) -78 deg C - RT, 2.) RT, overnight 3: 48 percent / tri-n-butyltin azide / xylene / 1.) 120 deg C, 60 h, 2.) 130 deg C, 4 h View Scheme

1: boron tribromide / CH2Cl2 / 1.) -78 deg C - RT, 2.) RT, overnight 2: 48 percent / tri-n-butyltin azide / xylene / 1.) 120 deg C, 60 h, 2.) 130 deg C, 4 h View Scheme