Samarium (II) iodide in conjunction with a catalytic low-valent transition metal species has been employed to promote the conjugate addition reaction of primary and secondary alkyl halides onto α, β-unsaturated esters and amides. The method has been determined to be quite general and hence has been extended to the cyclization reactions of alkyl halides onto α, β-unsaturated lactones, lactams, and nitriles. The cyclization reactions described herein ...