Warming a solution of the palladium alkyl olefin chelate complex 1 at −41 °C for 2 h led to intramolecular β-migratory insertion to form complex 2 as the exclusive product by 1H NMR spectroscopy. Conversion of 1 to 2 at −41 °C obeyed first-order kinetics to ≥3 half-lives with a rate constant of k = (4.7 ± 0.3) × 10-4 M s-1 (ΔG⧧ = 17.1 ± 0.1 kcal mol-1).
Warming a solution of {(phen)Pd[η1:η2-CH(CH2SiEt3)CH2C(CO2Me)2CH2CHCH2]}+[BAr4]- (4)at −41 °C led to first-order decay (k = (4.7 ± 0.3) × 10-4M s-1, ΔG⧧ = 17.1 ± 0.1 kcal mol-1) with formation ofthe palladium cyclopentylmethyl complex (5) in 96 ± 10% yield (1H NMR).