91760-38-2Relevant articles and documents
Synthesis, characterization, and rearrangements of [(1-methylcyclobutyl)methyl]platinum(II) complexes. Very mild ring-strain-induced carbon-carbon activation
Flood, Thomas C.,Statler, John A.
, p. 1795 - 1803 (1984)
Complexes trans-Pt(PMe3)2ClR, where R = (1-methylcyclobutyl)methyl (mcbm, 1), (adamantyl)methyl (adm, 8), 4-methylpentyl-1,1-d2 (9), and 4-methyl-4-pentenyl (10), and also PtCl(dmpe)(mcbm) [dmpe = 1,2-bis(dimethylphosphmo)ethane] (2) have been prepared. Pyrolysis of 1 or 2 at 140°C yields 2-methyl-1,4-pentadiene (12) as the only organic product, and trans-HPt(PMe3)2Cl (13) is isolated in high yield in the case of 1. Added PMe3 retards the pyrolysis of 1, leading to formation of [HPt(PMe3)3]Cl (14) and exhibiting kinetics consistent with initial PMe3 dissociation. Decomposition of 8 requires heating at 240°C for hours. Pyrolysis of 9 at 140°C forms 13 and 4-methyl-1-pentene-1,1-d2 with very little rearrangement of the deuterium label. Treatment of 1 with Ag+ in acetone at -80°C forms [trans-Pt(PMe3)2(mcbm)(acetone)]+ (15) that rearranges above -40°C to {cis-Pt(PMe3)2[1,4,5-n-(CH2) 3C(Me)=CH2]}+ (16) and above -10°C to a mixture of [Pt(PMe3)2(2-4-n-2-methylpentenyl)]+ (17a) and [Pt(PMe3)2(1-3-n-2-methylpentenyl)]+ (17b), which is isolated as the PF6- salt. Reaction of 1 with Ag+ in CD2Cl2 at -80 °C leads within 30 min to direct formation of 16, representing an extremely mild C-C activation step. Reaction of 10 with Ag+ at -80°C followed by warming to -20°C also generates 16. In contrast, 8 and Ag+ from [Pt(PMe3)2(adm)(acetone)]+ which is isolable at ambient temperature. Mechanistic implications of these reactions are discussed.
