Inherent Asymmetry of Constitutionally Equivalent Methyl Groups in the H/D Equilibration ofn- andi-C3H7Fe(OH)+ Complexes

Abstract

Dedicated to Graham Cooks on the occasion of his 60th birthday Reversible b-hydrogen transfer, a key reaction in organometallic chemistry, often relies on an alignment of the alkyl residue in terms of an agostic interaction (Scheme 1). Here, Scheme 1. Reversible b-hydrogen transfer with an agostic interaction.

C–H Bond Activation ofMethane with Gaseous [(CH3)Pt(L)]+ Complexes (L = Pyridine, Bipyridine, and Phenanthroline)

“…Of For a more detailed analysis of the exchange kinetics, the pressure dependence of the reactions was studied in order to evaluate thermal rate constants as well as accurate branching ratios [20]. Note that consideration of the pressure dependence is particularly important in the case of a degenerate isotope exchange as studied here, because CD 4 is leaked into the hexapole reaction cell at a constant pressure, whereas any CH n D 4−n isotopologs (n = 1 -3) formed in the reaction with the [(CH 3 )Pt(L)] + complexes are rapidly pumped away.…”

C–N coupling in the gas-phase reactions of ammonia and [M(CH)]+ (M = Ni, Pd, Pt): a combined experimental/computational exercise

“…Maximum yields of the desired complexes were achieved by adjusting the cone voltage (U c ); U c determines the degree of collisional activation of the incident ions in the transfer from the ESI source to the mass spectrometer. 11 The identity of the ions was confirmed by comparison with the expected isotope patterns. 12 The ion/molecule reactions of the complexes with ammonia were probed at a collisional energy (E lab ) set to nominally 0 eV, which in conjunction with the ca.…”

“…11 Millimolar solutions of [Ni-(CH 3 COO) 2 ] and [Pt 4 (CH 3 COO) 8 ] in pure methanol were used for the production of [M(CH)] + . 7 The solutions were introduced through a fused-silica capillary to the ESI source via a syringe pump (ca.…”

Michael additions catalyzed by transition metals and lanthanides species. A review. Part 1. Transition metals

“…Direct experimental evidence of the in situ formation of iron enolates has been provided recently by an ESI-MS study. 66 Moreover, ions containing iron and neutral, non-deprotonated ketoesters are also formed under ESI-MS conditions.…”