Thermal decomposition studies of bis(1-alkenyl)platinum(II) complexes of the type Pt(L2)R2 (where L = PPh3 or L2 = dppe or dppp; R = 1-alkenyl) are reported. The results revealed interesting organic product distributions depending on the length of the alkenyl chains, the nature of the supporting ligands and the metal centers. It is believed that the major decomposition pathways for the title complexes involve β-hydride elimination and/or reductive elimination as well as alkene isomerization. Mechanisms for the major and minor decomposition pathways are proposed. The amount of isomeric products obtained, i.e., 2-alkenes and 1,(n - 2)-diene, increases with increasing chain length. © 2008 Elsevier B.V. All rights reserved.