Triflate in RuH(OTf)(CO)L2 (L = PtBu2Me) can be abstracted by NaBAr′4 (Ar′ = C6H3-(CF3)2) in C6H5F to give 14-electron RuH(CO)L2+, which has agostic donation by one tBu methyl group from each phosphine. This cation binds CH2Cl2 in an η2 fashion, and it binds OEt2 and H2O in the site trans to CO. It binds ethylene trans to hydride, and additional ethylene is catalytically dimerized to cis- and trans-but-2-ene at -30°C in C6H5F/toluene; this dimerization is slower in CH2Cl2 solvent. Propylene and H2C=CHF also bind to RuH-(CO)L2+ trans to hydride, and the latter is converted to ethylene and Ru/F products. Vinyl ethers seem to bind η1 via ether oxygen more than η2 via the CC bond, and trans to CO, and this species then isomerizes to the RuL2(CO)(η2-CH2CH2OR) insertion product at -60°C. In contrast, 2,3-dihydrofuran gives a cyclic oxygen-stabilized carbene complex. A discussion of the results based on DFT (B3PW91) calculations is presented in the following paper.