An orbital deletion procedure (ODP) at HF/6-311G{*}{*} have been used to evaluate the hyperconjugation effects in the cyclopropylcarbinyl cation (1) and in cyclopropylborane (2), as well as the conjugation effects in the allyl cation (3) and in vinylborane (4). The hyperconjugation (or conjugation) energies have been quantified by ODP in which the critical "vacant" carbocation (or boron) p orbital is "deactivated". Comparisons between the bisected conformations of 1 with 3, and 2 with 4 demonstrate that cyclopropane can be just as effective as a pi-electron donor as a C=C double bond. (C) 1997 Elsevier Science B.V
A survey of the available data on the properties of cyclopropane systems shows that the common assum...
Computed aromatic stabilization energies (ASEs) and dissected nucleus independent chemical shifts (N...
The conformations of dicyclopropyl, isopropyl cyclopropyl, and diisopropylcarbenes were optimized us...
An orbital deletion procedure (ODP), which inactivates a critical pi orbital and therefore interrupt...
Hyperconjugation and its relationship with the 1,2-shift rearrangement reactivity in bicyclo[2.1.0]...
Hyperconjugation and its relationship with the 1,2-shift rearrangement reactivity in bicyclo[2.1.0]p...
Recent studies of nuclear spin polarization effects in cyclopropane derivatives have provided consid...
The rotational barriers of BD2 in B2D4 (D=H, F, OH, NH2, and CH3) are examined in terms of conjugati...
International audienceCarbocations can appear as transient species, for instance, in elimination rea...
B3LYP and MP2 quantum chemical calculations on cyclopropylcarbinyl cations fused to various cyclic a...
MO computations of " hard " (eg H +) and " soft " (eg SO 2) electrophiles reacting with substituted ...
International audienceThe geometry of ethyl cation is discussed, and the hyperconjugation effect in ...
higher temperatures ring opening reactions leading to more highly substituted allyl cations took pla...
Hyperconjugative stabilization of positive charge in tertiary carbocations is the textbook explanati...
There is considerable evidence that compounds in which a cyclopropane ring is located adjacent to an...
A survey of the available data on the properties of cyclopropane systems shows that the common assum...
Computed aromatic stabilization energies (ASEs) and dissected nucleus independent chemical shifts (N...
The conformations of dicyclopropyl, isopropyl cyclopropyl, and diisopropylcarbenes were optimized us...
An orbital deletion procedure (ODP), which inactivates a critical pi orbital and therefore interrupt...
Hyperconjugation and its relationship with the 1,2-shift rearrangement reactivity in bicyclo[2.1.0]...
Hyperconjugation and its relationship with the 1,2-shift rearrangement reactivity in bicyclo[2.1.0]p...
Recent studies of nuclear spin polarization effects in cyclopropane derivatives have provided consid...
The rotational barriers of BD2 in B2D4 (D=H, F, OH, NH2, and CH3) are examined in terms of conjugati...
International audienceCarbocations can appear as transient species, for instance, in elimination rea...
B3LYP and MP2 quantum chemical calculations on cyclopropylcarbinyl cations fused to various cyclic a...
MO computations of " hard " (eg H +) and " soft " (eg SO 2) electrophiles reacting with substituted ...
International audienceThe geometry of ethyl cation is discussed, and the hyperconjugation effect in ...
higher temperatures ring opening reactions leading to more highly substituted allyl cations took pla...
Hyperconjugative stabilization of positive charge in tertiary carbocations is the textbook explanati...
There is considerable evidence that compounds in which a cyclopropane ring is located adjacent to an...
A survey of the available data on the properties of cyclopropane systems shows that the common assum...
Computed aromatic stabilization energies (ASEs) and dissected nucleus independent chemical shifts (N...
The conformations of dicyclopropyl, isopropyl cyclopropyl, and diisopropylcarbenes were optimized us...