Modeling Ar and Kr matrix effect on the ν s (Cl–H) and ν l (Cl–H) of Cl–H···NH3 by the IEF-PCM method

Abstract

Ar and Kr matrix effect on the geometry and Cl-H stretching (m s (Cl-H)) and librational (m l (Cl-H)) frequencies of the hydrogen-bonded complex Cl-HÁÁÁNH 3 are simulated within the framework of polarizable continuum model with integral equation formalism (IEF-PCM) at B3LYP and MP2 levels of theory with the basis set 6-311++G(2df,2pd). Within the framework of B3LYP and IEF-PCM, the simulated gas phase, Ar, and Kr matrix m s (Cl-H) of the complex are 2140, 1684, and 1550 cm -1 , respectively, which deviate from the experimental values (*2200, 1371, and 1218 cm -1 ) by -60, 313, and 332 cm -1 . Within the framework of MP2 and IEF-PCM, the gas phase, Ar, and Kr matrix m s (Cl-H) are calculated as 2366, 2037, and 1957 cm -1 by the harmonic approximation, and as 2177, 1876, and 1665 cm -1 by the full-dimensional anharmonic correction. The matrix effect modeling is of greater importance than the anharmonic correction in accounting for the large experimental gas phase to Ar or Kr matrix shift of the m s (Cl-H) (-829 or -982 cm -1 ). Our calculations do not support the assignment of the 733.8 and 736.9 cm -1 bands to the Ar and Kr matrix m l (Cl-H).Keywords B3LYP and MP2 calculations Á IEF-PCM Á Argon and krypton matrix effect Á Anharmonic frequencies Á Ammonia-hydrogen chloride complex

Oxime‐Derived Iminyl Radicals in Selective Processes of Hydrogen Atom Transfer and Addition to Carbon‐Carbon π‐Bonds

“…[76] Some studies, however, showed that 1,3-HAT is possible in the presence of certain catalysts. [95][96][97][98][99][100][101][102][103][104][105][106] It should be noted that copper catalysis was involved in most examples where 1,3-HAT was supposed to have occurred with oxime-derived iminyl radicals.…”

“…The oxidative intermolecular cyclization of oxime acetates 73 and 2-aminobenzyl alcohols 74 in the presence of copper (II) acetate and sodium tertbutylate with the formation of quinolines 75 was developed (Scheme 28). [103] The authors proposed a catalytic cycle in which oxime acetate 73 is reduced by copper (I) with the formation of iminyl radical A. formation of the iminyl radicals from oxime esters 76 under the action of Fe II , followed by 1,3-HAT. The resulting C-centered radical attacks silyl enolate 77, then cyclization to product 78 occurs with the elimination of TMSOAc and H 2 O.…”

“…The oxidative intermolecular cyclization of oxime acetates 73 and 2‐aminobenzyl alcohols 74 in the presence of copper (II) acetate and sodium tert ‐butylate with the formation of quinolines 75 was developed (Scheme 28). [103] The authors proposed a catalytic cycle in which oxime acetate 73 is reduced by copper (I) with the formation of iminyl radical A . The latter is converted to iminylcopper (II) intermediate B , which further tautomerizes into copper (II) enamide C .…”

Interplay of thermochemistry and Structural Chemistry, the journal (volume 19, 2008) and the discipline

“…In the next paper, Liu et al [225] report on the modeling of argon and krypton matrix effect on the geometry and stretching, librational and anharmonic frequencies of the ammonia-hydrogen chloride complex with integral equation formalism (IEF-PCM) at B3LYP and MP2 levels of theory. The binding energy of both ammonia and ammonium ion to single and multiple argon atoms has been theoretically studied [226].…”