TY - JOUR
T1 - Singlet-triplet splittings and 1,2-hydrogen shift barriers for methylphenylborenide, methylphenylcarbene, and methylphenylnitrenium in the gas phase and solution. What a difference a charge makes
AU - Cramer, Christopher J.
AU - Truhlar, Donald G.
AU - Falvey, Daniel E.
PY - 1997/12/17
Y1 - 1997/12/17
N2 - In the isoelectronic series methylphenylborenide, methylphenylcarbene, and methylphenylnitrenium, fundamental differences are predicted for singlet state geometries, singlet-triplet state splittings, barriers to singlet 1,2- hydrogen migration, and sensitivity of 1,2-hydrogen migration to solvent effects in n-heptane and acetonitrile. We conclude that isoelectronic analogies are dangerous for systems having different formal charges, and that the interaction of the divalent center with a conjugating substituent is very sensitive to the electron donating or withdrawing nature (and power) of the hypovalent atom. Solvent effects on the singlet-triplet splitting result from static polarity differences whereas the solvent effects on 1,2-hydrogen migration result primarily from polarizability differences. For the experimentally characterized carbene case, extensive comparison of calculated and measured results is provided.
AB - In the isoelectronic series methylphenylborenide, methylphenylcarbene, and methylphenylnitrenium, fundamental differences are predicted for singlet state geometries, singlet-triplet state splittings, barriers to singlet 1,2- hydrogen migration, and sensitivity of 1,2-hydrogen migration to solvent effects in n-heptane and acetonitrile. We conclude that isoelectronic analogies are dangerous for systems having different formal charges, and that the interaction of the divalent center with a conjugating substituent is very sensitive to the electron donating or withdrawing nature (and power) of the hypovalent atom. Solvent effects on the singlet-triplet splitting result from static polarity differences whereas the solvent effects on 1,2-hydrogen migration result primarily from polarizability differences. For the experimentally characterized carbene case, extensive comparison of calculated and measured results is provided.
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U2 - 10.1021/ja9723390
DO - 10.1021/ja9723390
M3 - Article
AN - SCOPUS:0031576652
SN - 0002-7863
VL - 119
SP - 12338
EP - 12342
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 50
ER -