TY - JOUR
T1 - Intramolecular triarylmethane-triarylmethylium complexes with a naphthalene-1,8-diyl skeleton
T2 - Isolation, structure, and reactivities of the C-H-bridged carbocations
AU - Takeda, Takashi
AU - Kawai, Hidetoshi
AU - Fujiwara, Kenshu
AU - Suzuki, Takanori
PY - 2007/10/16
Y1 - 2007/10/16
N2 - Isolation and low-temperature X-ray analyses of intramolecular triarylmethane-triarylmethylium complexes with a naphthalene- 1,8-diyl-type skeleton have been achieved. These bridged cations prefer a C-H localized structure both in solution and in the solid state. The bridging hydrogen undergoes a facile intramolecular 1.5-hydride shift from one carbon to another in solution. The C-H delocalized geometry is suggested to be the transition-state structure of the degenerate rearrangement. Charge-transfer interaction from the triarylmethane to the triarylmethylium units is evident in the electronic spectra. This interaction stabilizes the present cations. Low reactivity toward Brønsted acids indicates that these species are not the reaction intermediates in the acid-assisted longbond cleavage of 1,1,2,2-tetraarylacenaphthene derivatives.
AB - Isolation and low-temperature X-ray analyses of intramolecular triarylmethane-triarylmethylium complexes with a naphthalene- 1,8-diyl-type skeleton have been achieved. These bridged cations prefer a C-H localized structure both in solution and in the solid state. The bridging hydrogen undergoes a facile intramolecular 1.5-hydride shift from one carbon to another in solution. The C-H delocalized geometry is suggested to be the transition-state structure of the degenerate rearrangement. Charge-transfer interaction from the triarylmethane to the triarylmethylium units is evident in the electronic spectra. This interaction stabilizes the present cations. Low reactivity toward Brønsted acids indicates that these species are not the reaction intermediates in the acid-assisted longbond cleavage of 1,1,2,2-tetraarylacenaphthene derivatives.
KW - Carbocations
KW - Charge transfer
KW - Hydride shift
KW - Neighboring-group effects
KW - Pen-interactions
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U2 - 10.1002/chem.200700803
DO - 10.1002/chem.200700803
M3 - Article
C2 - 17722210
AN - SCOPUS:35048833788
VL - 13
SP - 7915
EP - 7925
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
SN - 0947-6539
IS - 28
ER -