A Quantum Chemical Study on the Interconversion Mechanism between Double-substituted Ammonium Oxide and Double-substituted Hydroxylamine

作者：Shi Guo Sheng^*; Ding Yi Hong

来源：Acta Chimica Sinica, 2008, 66(22): 2483-2488.

• R(2)HNO
• R(2)NOH
• isomer
• thermodynamic stability
• dynamic stability

At the B3LYP/6-311 + +G(d,p) level, the first time computational study was performed on the interconversion mechanism between a series of double-substituted ammonium oxide (R(2)HNO) and double-substituted hydroxylamine (R(2)NOH) isomers with R=CH(3), NH(2), OH, F, CH(2)CH(3), CH(CH(3))(2) and C(CH(3))(3). Comparisons were made with the mechanism of H(3)NO and H(2)NOH, It was shown that relative to the double-substitued hydroxylamine (R(2)NOH), the increase of the electronegativity of R in the order of H< CH(3)<NH(2)<OH<F could raise both the thermodynamic and kinetic stability of the double-substituted ammonium oxide (R(2)HNO). In addition, for the alkyl substituents R [R=CH(3), CH(2)CH(3), CH(CH(3))(2) and C(CH(3))(3)], the greater steric effect would result in the higher thermodynamic stability, and also certainly increased kinetic stability, though not so noticeable. For the newly considered seven substituents [R=CH(3), NH(2), OH, F, CH(2)CH(3), CH(CH(3))(2) and C(CH(3))(3)], the conversion barrier from R2HNO to R2NOH is as large as 27.0 similar to 56.3 kcal/mol. This indicates that all of them might be probably characterized in gas-phase.

• 出版日期2008-11-28
• 单位吉林大学