Theoretical Studies of Amino Acid Formation in the Interstellar Medium: Reactions of Formic Acid with Methylenimine and Related Cations

抄録

  To evaluate feasibility of the gas-phase formation of glycine in dense interstellar clouds from formic acid, methylenimine and related cations, main stationary points for the reactions HN＝CH₂ + HCOOH → H₂N―CH₂―COOH, HN⁺CH + HCOOH → HN⁺―CH₂―COOH and H₂N⁺＝CH₂ + HCOOH → H₂N⁺―CH₂―COOH have been computed at the B3LYP/6-31++G(d,p) level of theory. Although all the reactions are exothermic, they are prohibited due to the presence of transition states with positive relative energies of ＞40 kcal mol^-1 and the possibility of competitive formation of side products.