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Common Radical Cation Intermediates in Cage Hydrocarbon Activations
Author(s) -
Fokin Andrey A.,
Gunchenko Pavel A.,
Peleshanko Sergey A.,
Schleyer Paul von Ragué,
Schreiner Peter R.
Publication year - 1999
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/(sici)1099-0690(199904)1999:4<855::aid-ejoc855>3.0.co;2-7
Subject(s) - chemistry , electrophile , radical ion , density functional theory , adamantane , computational chemistry , ab initio , electrochemistry , singlet state , ionization energy , hydrocarbon , ionization , photochemistry , ion , organic chemistry , electrode , excited state , physics , nuclear physics , catalysis
Abstract The oxidation of 3,6‐dehydrohomoadamantane ( 1 ) was achieved under chemical (NO + BF 4 – /EtOAc, NO + OAc – /Ac 2 O, and NO + BF 4 – /CH 3 CN), photochemical (photoexcited 1,2,4,5‐tetracyanobenzene), and electrochemical (Pt anode, CH 3 CN, NH 4 BF 4 ) conditions. Supporting ab initio [density functional theory (BLYP) and Møller–Plesset perturbation theory (MP2)] computations utilizing standard basis sets, 6–31G* (optimizations) and 6–311+G* (single‐point energy evaluations), agree with the experimental results implicating the involvement of the same radical cation intermediates in the activation processes. Isomeric radical cations formed from different precursors can equilibrate with low barriers (2.0–11.7 kcal mol –1 ) and lead to common products. The computed and experimental adiabatic ionization potential of adamantane shows that activation with NO + BF 4 – is also likely to occur through the adamantyl radical cation. Hence, the bonds need not be attacked directly by the electrophile in the C–H or C–C activation of alkanes with relatively low ionization potentials.