in dichloromethane 20 h; Heating;

1: 99 percent / CH2Cl2 / 20 h / Heating 2: 1.) Ph3SnH, azo-bis(isobutyronitrile), 2.) 80percent AcOH-H2O / 1.) reflux, benzene, 20 h, 2.) 1 h View Scheme