Pd(0)-catalyzed Mizoroki-Heck alkenylations and arylations of protected aminocyclopentenes, prepared in a few steps from Vince lactam, afforded functionalized cyclopentenes in high yields and stereoselectivities. DFT calculations were performed to rationalize the high diastereoselectivities. Functionalized cyclopentene products were transformed into valuable chiral building blocks, such as cyclic γ-amino acids and carbocyclic nucleoside precursors.