2,2'-azo-bisisobutyronitrile; tri-n-butyl-tin hydride in cyclohexane T=75°C; 0.75 h; further reagent: Zn(BH4)2/ether; Yield given. Yields of byproduct given;

1: 72 percent / hydrogen chloride / CH2Cl2 / -78 °C 2: azoisobutyronitrile, tributyltin hydride / cyclohexane / 0.75 h / 75 °C / further reagent: Zn(BH4)2/ether View Scheme