TY - JOUR
T1 - Valence isomerism and rearrangements in methanofullerenes
AU - Diederich, François
AU - Isaacs, Lyle
AU - Philp, Douglas
PY - 1994
Y1 - 1994
N2 - A PM3 computational and experimental study of the methanofullerenes 1-5 demonstrates that the electronic basis for the experimentally preferred formation of the [6,6]-closed and [6,5]-open over the [6,6]-open and [6,5]-closed isomers of methanofullerenes is the preservation of the [5]radialene-type bonding pattern found in C60 by these two structures. The [6,5]-open is the less stable of the two experimentally isolated isomers as a result of the violation of Bredt's Rule. The PM3 method locates a [6,5]-closed structure for the methanofullerenes 2-5, but not for 1. This suggests that the thermal interconversion of the [6,5]-open and [6,6]-closed isomers can only occur via a stepwise mechanism - [6,5]-open to [6,5]-closed valence isomerisation followed by a 1,5-shift - in cases where the corresponding [6,5]-closed structure is located in a local energy minimum.
AB - A PM3 computational and experimental study of the methanofullerenes 1-5 demonstrates that the electronic basis for the experimentally preferred formation of the [6,6]-closed and [6,5]-open over the [6,6]-open and [6,5]-closed isomers of methanofullerenes is the preservation of the [5]radialene-type bonding pattern found in C60 by these two structures. The [6,5]-open is the less stable of the two experimentally isolated isomers as a result of the violation of Bredt's Rule. The PM3 method locates a [6,5]-closed structure for the methanofullerenes 2-5, but not for 1. This suggests that the thermal interconversion of the [6,5]-open and [6,6]-closed isomers can only occur via a stepwise mechanism - [6,5]-open to [6,5]-closed valence isomerisation followed by a 1,5-shift - in cases where the corresponding [6,5]-closed structure is located in a local energy minimum.
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U2 - 10.1039/p29940000391
DO - 10.1039/p29940000391
M3 - Article
AN - SCOPUS:37049080793
SP - 391
EP - 394
JO - Journal of the Chemical Society, Perkin Transactions 2
JF - Journal of the Chemical Society, Perkin Transactions 2
SN - 1470-1820
IS - 3
ER -