The formal syntheses of hirsutine (1) and rhynchophylline (2) are described. Our approach features the use of ring-closing metathesis (RCM) to construct an α,β-unsaturated lactam, which undergoes subsequent 1,4-addition. Nucleophilic additions into non-activated α,β-unsaturated amides and lactams are generally considered problematic, but we have demonstrated that the lithium enolate of ethyl-1,3-dithiolane carboxylate undergoes diastereoselective 1,4-additions to lactams such as 3.