4-Substituted tert-Butyl Phenylazocarboxylates-Synthetic Equivalents for the para-Phenyl Radical Cation

2010 ◽  
Vol 49 (50) ◽  
pp. 9769-9772 ◽  
Author(s):  
Sarah B. Höfling ◽  
Amelie L. Bartuschat ◽  
Markus R. Heinrich
Keyword(s):  
Radical Cation ◽  
Phenyl Radical ◽  
Tert Butyl

ChemInform Abstract: 4-Substituted tert-Butyl Phenylazocarboxylates-Synthetic Equivalents for the para-Phenyl Radical Cation.

ChemInform ◽  
2011 ◽  
Vol 42 (15) ◽  
pp. no-no
Author(s):  
Sarah B. Hoefling ◽  
Amelie L. Bartuschat ◽  
Markus R. Heinrich
Keyword(s):  
Radical Cation ◽  
Phenyl Radical ◽  
Tert Butyl

Effects of Ultrasounds on Neat nitrobenzene

2019 ◽  
Vol 70 (8) ◽  
pp. 3085-3088
Author(s):  
Carmen Eugenia Stavarache ◽  
Yasuaki Maeda ◽  
Mircea Vinatoru
Keyword(s):  
Nitro Group ◽  
Radical Cation ◽  
Reaction Mechanisms ◽  
Diphenyl Ether ◽  
Argon Atmosphere ◽  
Phenyl Radical ◽  
Dissolved Gas ◽  
Decomposition Products ◽  
Oxygenated Compounds ◽  
Phenyl Cation

Neat nitrobenzene was continuously irradiated at two ultrasonic frequencies: 40 and 200 kHz, under air and argon atmosphere, respectively. Samples taken at intervals of 1, 5, 10 and 24 h were analyzed by GC-MS and decomposition products were identified. Possible reaction mechanisms are discussed. Presence of air as dissolved gas leads to oxygenated compounds such as 1,4-benzoquinone, 2,4-dinitrophenol, m-dinitrobenzene while argon inhibits the decomposition of nitrobenzene, especially at sonication times under 5 h. Based on the nature of the compounds identified we advanced a mechanism, involving a divergent splitting of unstable radical cation of NB in air and argon respectively. Thus, under air, the phenyl cation formation is preferred leading to 1,4-benzoquinone nitro-biphenyls and dinitrobenzene, while under argon, the phenyl radical formation seems to be favored, leading to phenol and diphenyl ether. The oxygenated compounds detected under argon clearly are a consequence of the nitro group splitting.

Cleavage of the radical cations of alkenes; 1-butene and 4,4-dimethyl-1-pentene. Ab initio calculations on the interaction between the allyl and alkyl radical and carbocation moieties

1991 ◽  
Vol 69 (9) ◽  
pp. 1365-1375 ◽  
Author(s):  
Xinyao Du ◽  
Donald R. Arnold ◽  
Russell J. Boyd ◽  
Zheng Shi
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Radical Cation ◽  
Alkyl Radical ◽  
Radical Cations ◽  
Molecular Orbital Calculations ◽  
Allyl Radical ◽  
Allyl Cation ◽  
Tert Butyl ◽  
Carbon Carbon Bond

Carbon–carbon bond cleavage of the radical cations of 1-butene [Formula: see text] and 4,4-dimethyl-1-pentene [Formula: see text] will generate the allyl and alkyl radical and carbocation fragments. Alternative bonding arrangements between the allyl and methyl moieties in [Formula: see text] and between the allyl and tert-butyl moieties in [Formula: see text] possible metastable intermediates or transition states preceding complete separation of the fragments, have been investigated by ab initio molecular orbital calculations. Structures were fully optimized at the UHF/6-31G* or UHF/STO-3G levels, and some of the calculations on [Formula: see text] were expanded with single point MP2/6-31G*//UHF/6-31G* computations. The C4H8+ radical cation, having a structure similar to that of 1-butene, is more stable than the separated fragments: 183 kj mol−1 lower in energy than the sum of the energies of the allyl cation and the methyl radical, and 385 kJ mol−1 lower than the sum of the energies of an allyl radical and a methyl cation, at the MP2/6-31G* level. The corresponding values at the UHF/STO-3G level are 276 and 415 kj mol−1, respectively. There is less bonding interaction between the allyl and tert-butyl moieties in [Formula: see text] The summation of the energies of the allyl radical and tert-butyl cation is 123 kj mol−1 lower than the summation of the energies of the allyl cation and tert-butyl radical, and 115 kJ mol−1 higher in energy than the bonded radical cation [Formula: see text] at the UHF/STO-3G level. These calculated values are compared with thermochemical data and with experimental results on the cleavage of these, and related, radical cations. Key words: radical cation, cleavage, ab initio calculations, electron transfer, photochemistry.

Reversible electrochemical oxidation of 2,5,8,11-tetra-tert-butyl-peri-xanthenoxanthene to its radical cation and dication

1988 ◽  
Vol 29 (36) ◽  
pp. 4533-4534 ◽  
Author(s):  
Alwin Dettling ◽  
Anton Rieker ◽  
Bernd Speiser
Keyword(s):  
Electrochemical Oxidation ◽  
Radical Cation ◽  
Tert Butyl

2,5,8,11-Tetra-tert-butyl-peri-xanthenoxanthene and its Dication Spectroelectrochemistry and Model Calculations on a Dioxa-22-π-system

1996 ◽  
Vol 51 (3) ◽  
pp. 377-380 ◽  
Author(s):  
Gernot Frenking ◽  
Anton Rieker ◽  
Josef Salbeck ◽  
Bernd Speiser
Keyword(s):  
Ab Initio ◽  
Radical Cation ◽  
Bathochromic Shift ◽  
Quantum Mechanical ◽  
Quantum Mechanical Calculations ◽  
Model Calculations ◽  
Tert Butyl ◽  
Model Structures

Abstract Spectroelectrochemistry of 2,5,8,1 1-tetra-tert-butyl-peri-xanthenoxanthene 1 yields the UV/VIS spectra of the corresponding radical cation 1+ and dication 12+. The bathochromic shift for the dication 12+ relative to 1 and to the isoelectronic hydrocarbon anthanthrene (2) can be understood by quantum mechanical calculations (ab initio, AM1) of model structures.

Phenyl Radical, Cation, and Anion. The Triplet−Singlet Gap and Higher Excited States of the Phenyl Cation

1997 ◽  
Vol 119 (34) ◽  
pp. 8083-8088 ◽  
Author(s):  
Athanassios Nicolaides ◽  
David M. Smith ◽  
Frank Jensen ◽  
Leo Radom
Keyword(s):  
Excited States ◽  
Radical Cation ◽  
Phenyl Radical ◽  
Phenyl Cation ◽  
Higher Excited States
Sign in / Sign up

Export Citation Format

Share Document