A Host-Induced Intramolecular Charge-Transfer Complex and Light-Driven Radical Cation Formation of a Molecular Triad with Cucurbit[8]uril

2008 ◽  
Vol 73 (10) ◽  
pp. 3775-3783 ◽  
Author(s):  
Dapeng Zou ◽  
Samir Andersson ◽  
Rong Zhang ◽  
Shiguo Sun ◽  
Björn Åkermark ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Radical Cation ◽  
Charge Transfer Complex ◽  
Intramolecular Charge Transfer

Photochemical Nitration by Tetranitromethane. XVII. The Regiochemistry of Adduct Formation in the Photochemical Reaction of 1-Methylnaphthalene and Tetranitromethane

1994 ◽  
Vol 47 (8) ◽  
pp. 1591 ◽  
Author(s):  
JL Calvert ◽  
L Eberson ◽  
MP Hartshorn ◽  
n Maclaga ◽  
WT Robinson
Keyword(s):  
Crystal Structure ◽  
Charge Transfer ◽  
Radical Cation ◽  
Photochemical Reaction ◽  
Charge Transfer Complex ◽  
Adduct Formation ◽  
X Ray ◽  
Analogous Manner ◽  
Structure Determinations ◽  
Ion Recombination

Photolysis of the 1-methylnaphthalene/tetranitromethane charge-transfer complex yields the triad of 1-methylnaphthalene radical cation, nitrogen dioxide and trinitromethanide ion. Recombination of this triad gives predominantly 4-methyl-t-2-nitro-r-1-trinitromethyl-1,2- dihydronaphthalene (1), the epimeric 1-methyl-1-nitro-4-trinitromethyl-1,4-dihydronaphtha-lenes (2) and (3), 8-methyl-c-4-trinitromethyl-1,4-dihydronaphthalen-r-l-ol (4), nitro cyclo -adduct (5), 8-methyl-c-4-trinitromethyl-1,4-dihydronaphthalen-r-l-ol (6), hydroxy cyclo-adduct (7) and 4-methyl-t-1-trinitromethyl-1,2-dihydronaphthalen-r-2-ol (8). Adducts (1)- (3), (5), (7) and (8) are formed by attack of the trinitromethanide ion at C4 of the 1-methylnaphthalene radical cation, while adducts (4) and (6) are formed by corresponding attack at C5. Adduct (1) undergoes thermal cycloaddition to give the nitro cycloadduct (5) and it is assumed that the hydroxy cycloadduct (7) is formed in analogous manner from 4-methyl-t-1-trinitromethyl-1,2-dihydronaphthalen-r-2-ol (8). X-Ray crystal structure determinations are reported for adducts (1), (3)-(5) and (7).

Photochemical Nitration by Tetranitromethane. XIV. The Formation of 1,3-Dipolar Nitro Addition Products From the Photochemical Reaction of 1,2-Dimethylnaphthalene and Tetranitromethane

1994 ◽  
Vol 47 (6) ◽  
pp. 1087 ◽  
Author(s):  
CP Butts ◽  
JL Calvert ◽  
L Eberson ◽  
MP Hartshorn ◽  
n Maclaga ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Nitrogen Dioxide ◽  
Radical Cation ◽  
Photochemical Reaction ◽  
Charge Transfer Complex ◽  
Ion Recombination

Photolysis of the 1,2-dimethylnaphthalene/tetranitromethane charge-transfer complex yields the triad of 1,2-dimethylnaphthalene radical cation, nitrogen dioxide, and trinitromethanide ion. Recombination of this triad gives predominantly the adducts (13)-(16), each of which is formed by attack of the trinitromethanide ion at C4 of the 1,2-dimethylnaphthalene radical cation. Thermal cycloaddition in adducts (13) and (16) gives the cycloadducts (12) and (17) respectively.

Study on excited states of hexamethoxybenzene-NO+ charge-transfer complex: incorporation of excited radical cation

2012 ◽  
Vol 39 (1) ◽  
pp. 425-435 ◽  
Author(s):  
Nobuyuki Ichinose ◽  
Masahide Hagiri ◽  
Jun-ichiro Kinugasa ◽  
Nobuyuki Shichi ◽  
Toshihiro Nakayama
Keyword(s):  
Charge Transfer ◽  
Excited States ◽  
Radical Cation ◽  
Charge Transfer Complex ◽  
Excited Radical

The photochemical nucleophile–olefin combination, aromatic substitution (photo-NOCAS) reaction (Part 4): methanol–olefins, methyl 4-cyanobenzoate

1993 ◽  
Vol 71 (4) ◽  
pp. 450-468 ◽  
Author(s):  
Kevin McMahon ◽  
Donald R. Arnold
Keyword(s):  
Charge Transfer ◽  
Radical Cation ◽  
Charge Transfer Complex ◽  
Cyano Group ◽  
Aromatic Substitution ◽  
Mixture Formation ◽  
Reaction Conditions ◽  
Aromatic Molecules ◽  
Aromatic Esters ◽  
Methanol Solutions

Dicyanobenzene-1,4 (1) and -1,2 are known to undergo substitution upon irradiation, in the presence of an olefin, in acetonitrile–methanol (3:1) solution. The products are 1:1:1 (methanol:olefin:aromatic) adducts, substituted on the aromatic ring with loss of a cyano group. This reaction, referred to as the photo-NOCAS (nucleophile–olefin combination, aromatic substitution) reaction, has been shown to be fairly general with regard to the olefin and the nucleophile that can be incorporated. Less is known about the scope of the reaction incorporating other electron-withdrawing substituted aromatic molecules. The purpose of this study was to determine if methyl 4-cyanobenzoate (10) would also take part in this reaction, to form 4-substituted aromatic esters. Irradiation of acetonitrile–methanol solutions of 10 and olefins 2,3-dimethyl-2-butene (2) and 1-methylcyclohexene (5) gave cyclic imine esters, 11 and 13, respectively, instead of photo-NOCAS products. The photo-NOCAS products were obtained when the codonor biphenyl (4) was added to the irradiation mixture. Formation of the cyclic imine ester is attributed to excitation of the charge-transfer complex formed between 10 and the olefin. The addition of biphenyl (4) serves to generate the contact radical ion pair (CRIP) upon irradiation of the charge-transfer complex between 10 and 4. This CRIP can dissociate to the solvent-separated radical ions, the radical cation of 4 can accept an electron from the olefin, and the olefin radical cation can go on to give the photo-NOCAS products. Irradiation of a solution of 10 and 2 in nonpolar solvent (benzene) gave the oxetane, believed to arise from the exciplex. In addition to photo-NOCAS products from 10, 4-cyanophenylketones 17 and 23 are also formed by attack of the β-alkoxyalkyl radical at the carboxyl carbonyl. The differences in behaviour between 1,4-dicyanobenzene (1) and methyl 4-cyanobenzoate (10) under these reaction conditions are described and explained.

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