title: Generalized anomeric effect on N-alkyl-amino cation affinities: a G2(+)M investigation.
abstract: The gas-phase N-alkyl-amino-cation affinities (NAACA) of archetypal anionic main-group element hydrides across the Periodic Table have been investigated by means of a modified G2(+) scheme. The reactions studied include R(2)NB → R(2)N(+) + B(-) (R = H, Me; B = XH(n), n = 0-3; X = F, Cl, Br, O, S, Se, N, P, As, C, Si, Ge). Our calculations indicate that the reasonable linear correlations between NAACA and proton affinities (PA) only exist within the Period 2 anions, including H(3)C(-), H(2)N(-), HO(-), and F(-), or the anions within Periods 3-4 in the Periodic Table, which is significantly different from the alkyl cation affinities, where there is a reasonable correlation between the computed alkyl cation affinity and PA values of the set of anionic main-group element hydrides. The interesting differences can be ascribed to the generalized anomeric effect induced by n(N) → σ*(X-H) negative hyperconjugation found in R(2)NXH(n), with central atom X belonging to Groups 14-16 (X = O, S, Se, N, P, As, C, Si, Ge).
authors.affiliation: College of Chemistry and Key State Laboratory of Biotherapy, Sichuan University, Chengdu 610064, China.
authors.forename: Song
authors.initials: S
authors.lastname: Geng
authors.forename: Yi
authors.initials: Y
authors.lastname: Ren
authors.forename: Ning-Bew
authors.initials: NB
authors.lastname: Wong
authors.forename: Wai-Kee
authors.initials: WK
authors.lastname: Li
mesh_terms: D000588:Amines / Q000737:chemistry*; D002412:Cations; D005740:Gases
chemical_list: D000588:Amines; D002412:Cations; D005740:Gases