The complexes (cod)MCl 2 (M ) Pd, Pt; cod ) cis,cis-1,5-cyclooctadiene) react with Li 2 (cot) (cot ) cyclooctatetraene) in a 1,6-diene/diethyl ether mixture (1,6-diene ) hepta-1,6-diene, diallyl ether, dvds (1,3-divinyl-1,1,3,3-tetramethyldisiloxane)) to afford the isolated homoleptic dinuclear Pd 0 and Pt 0 compounds Pd 2 (C 7 H 12 ) 3 (1), Pd 2 (C 6 H 10 O) 3 ‚C 6 H 10 O (2′; 2: Pd 2 (C 6 H 10 O) 3 ), Pd 2 (dvds) 3 (3), and Pt 2 (C 7 H 12 ) 3 (4). When 1-4 are treated with additional 1,6-diene the equally homoleptic but mononuclear derivatives of type M(1,6-diene) 2 (5-8) and with ethene the mixed alkene complexes (C 2 H 4 )M(1,6-diene) (9-12) are obtained in solution.Complexes 1-12 react with donor ligands such as phosphanes, phosphites, or t BuNC to give isolated complexes of types L-M(1,6-diene) (13-41), which have also been prepared by other routes. In all complexes the metal centers are TP-3 coordinated: complexes 1-4 contain chelating and bridging 1,6-diene ligands, whereas the other complexes contain a chelating 1,6-diene ligand and an η 2 -alkene (5-12) or η 1 -donor ligand (13-41). Of the studied 1,6-diene complexes the hepta-1,6-diene derivatives are most reactive, while the diallyl ether complexes are often more convenient to handle. The readily isolable dinuclear hepta-1,6-diene and diallyl ether complexes 1, 2′, and 4, and their mononuclear pure olefin derivatives are among the most reactive sources for naked Pd 0 and Pt 0 . The corresponding L-M(1,6-diene) complexes are equally reactive precursor compounds for the generation of [L-M 0 ] fragments in solution, which for M ) Pd are available otherwise only with difficulty. The results are significant for the operation of naked Pd 0 and L-Pd 0 catalysts in homogeneous catalysis.