195154-39-3Relevant academic research and scientific papers
Palladium migration along linear carbon chains: The detection of η1-η2-enyl intermediates and the study of their rearrangement
Albéniz, Ana C.,Espinet, Pablo,Lin, Yong-Shou
, p. 4138 - 4144 (2008/10/08)
The reactions of [PdPfBr(NCMe)2] (Pf = C6F5) with stoichiometric amounts of 1,5-hexadiene, 1,6-heptadiene, or 1,7-octadiene at low temperature result in the formation of several (η1-η2-enyl)palladium complexes that isomerize sequentially at different temperatures depending on the ring size of the palladacycles (Tisom: 7.5- 1-η2-enyl)palladium derivatives are intermediates in the Pd-migration process, arrested by coordination of the unattacked double bond. The final products of their isomerization are several isomeric Pf-(η3-allyl)palladium complexes (Pf = C6F5). The major allylic derivative in each case arises from Pd migration to the terminal double bond. Minor amounts of (η3-allyl)palladium complexes formed by double bond switches in the process of Pd migration are also seen, but this occurs only on putative 1,5- or 1,6-diene-hydrido-palladium intermediates. A small amount of cyclic organic derivatives coming from the cyclization of (η1-η2-enyl)palladium intermediates is detected in each case. The use of excess diolefin gives rise to additional (η3-allyl)palladium complexes without the Pf group and to the corresponding Pf-substituted linear dienes. These arise via displacement of the Pf dienes by the starting diolefin in a hydrido-palladium intermediate during the Pd-migration process.
