Nitrosation of malononitrile by HONO, ClNO and N₂O₃: a theoretical study.
Nitrosation reactions of malononitrile by three nitrosating agents, HONO, ClNO, and N(2)O(3), have been theoretically investigated at the B3LYP/cc-pVTZ and MP2/cc-pVDZ levels. Two possible competitive paths for nitrosation of malononitrile to give 2-nitroso-malononitrile were proposed: (a) direct C-nitrosation and (b) N-nitrosation and subsequent nitroso transfer from N to C atom. The calculations show that at both B3LYP and MP2 levels, path b is kinetically favored over path a for nitrosations by HONO and N(2)O(3). In the case of ClNO, the B3LYP predicts preference of path b, while the MP2 calculations suggest that both paths have similar rate-determining barriers. The data suggest that N(2)O(3) is the preferred nitrosating agent for the nitrosation of malononitrile in aqueous solution. Transformation of 2-nitroso-malononitrile to form malononitrileoxime via intramolecular proton transfer has also been explored, and it is found that inclusion of an assistant water molecule can drastically accelerate the tautomerization.
Yang
Kun
K
State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Chen
Xiao-Fang
XF
Liu
Jian-Yong
JY
Lai
Wei-Peng
WP
Wang
Bo-Zhou
BZ
D001688:Biological Products / Q000737:chemistry; D007536:Isomerism; D008956:Models, Chemical; D008962:Models, Theoretical; D009570:Nitriles / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D015538:Nitrosation; D009603:Nitroso Compounds / Q000737:chemistry*; D009608:Nitrous Acid / Q000737:chemistry*; D011522:Protons; D011789:Quantum Theory; D012996:Solutions; D013816:Thermodynamics; D014867:Water
D001688:Biological Products; D009570:Nitriles; D009589:Nitrogen Oxides; D009603:Nitroso Compounds; D011522:Protons; D012996:Solutions; D014867:Water; C031701:nitrogen trioxide; C000945:dicyanmethane; D009608:Nitrous Acid