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Oxidative Carbon−Carbon Bond Cleavage of a [2.2]Paracyclophane Derivative − Efficient Intramolecular Trapping of the Radical Cation

“…[1] Nitromethane was fractionally distilled and stored over freshly activated molecular sieves (type 4 Å ). Dichloromethane was distilled from CaH 2 under nitrogen.…”

Oxidative Carbon−Carbon Bond Cleavage of a [2.2]Paracyclophane Derivative − Efficient Intramolecular Trapping of the Radical Cation

“…[1] Nitromethane was fractionally distilled and stored over freshly activated molecular sieves (type 4 Å ). Dichloromethane was distilled from CaH 2 under nitrogen.…”

Novel ring-cleaving reaction of 4-nitro-1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane with nucleophiles

“…All other examples of ring-opening of [2.2]paracyclophanes have involved SET oxidation of PCP, processes that proceed via radical cation intermediates. Such radical cations have been generated either electrochemically [6], under Birch reduction conditions [7], or via treatment of PCP with cerium(IV) ammonium nitrate (CAN) [8] or the strong one-electron oxidant, nitrosonium tetrafluoroborate (NOBF 4 ) [9]. As exemplified by the reaction of PCP with CAN in Scheme 4, all of these oxidation reactions involve cleavage of the C 1 -C 2 benzylic bond of radical cation 3 to form the bis-benzylic distonic radical cation 4, which can be trapped either before of after a second oxidative step to form products such as 5.…”

The Phane Properties ofanti-[2.2](1,4)Biphenylenophane

“…For [2.2]paracyclophane bearing 31−33 kcal/mol of strain energy, cleavage of the ethano bridges is thermodynamically favorable due to ring opening and the release of associated strain, leading to benzyl−benzyl biradicals above 200 °C along with substantial chemical reactions, such as isomerization or racemization . In addition, the unusually long ethano bridges made the C−C bonds kinetically labile toward thermal dissociation.…”

Oxidative Carbon−Carbon Bond Cleavage of a [2.2]Paracyclophane Derivative − Efficient Intramolecular Trapping of the Radical Cation

“…[1] Nitromethane was fractionally distilled and stored over freshly activated molecular sieves (type 4 Å ). Dichloromethane was distilled from CaH 2 under nitrogen.…”

Novel ring-cleaving reaction of 4-nitro-1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane with nucleophiles

“…All other examples of ring-opening of [2.2]paracyclophanes have involved SET oxidation of PCP, processes that proceed via radical cation intermediates. Such radical cations have been generated either electrochemically [6], under Birch reduction conditions [7], or via treatment of PCP with cerium(IV) ammonium nitrate (CAN) [8] or the strong one-electron oxidant, nitrosonium tetrafluoroborate (NOBF 4 ) [9]. As exemplified by the reaction of PCP with CAN in Scheme 4, all of these oxidation reactions involve cleavage of the C 1 -C 2 benzylic bond of radical cation 3 to form the bis-benzylic distonic radical cation 4, which can be trapped either before of after a second oxidative step to form products such as 5.…”

The Phane Properties ofanti-[2.2](1,4)Biphenylenophane

“…For [2.2]paracyclophane bearing 31−33 kcal/mol of strain energy, cleavage of the ethano bridges is thermodynamically favorable due to ring opening and the release of associated strain, leading to benzyl−benzyl biradicals above 200 °C along with substantial chemical reactions, such as isomerization or racemization . In addition, the unusually long ethano bridges made the C−C bonds kinetically labile toward thermal dissociation.…”

Oxidative Carbon−Carbon Bond Cleavage of a [2.2]Paracyclophane Derivative − Efficient Intramolecular Trapping of the Radical Cation

“…[1] Nitromethane was fractionally distilled and stored over freshly activated molecular sieves (type 4 Å ). Dichloromethane was distilled from CaH 2 under nitrogen.…”

Novel ring-cleaving reaction of 4-nitro-1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane with nucleophiles

“…All other examples of ring-opening of [2.2]paracyclophanes have involved SET oxidation of PCP, processes that proceed via radical cation intermediates. Such radical cations have been generated either electrochemically [6], under Birch reduction conditions [7], or via treatment of PCP with cerium(IV) ammonium nitrate (CAN) [8] or the strong one-electron oxidant, nitrosonium tetrafluoroborate (NOBF 4 ) [9]. As exemplified by the reaction of PCP with CAN in Scheme 4, all of these oxidation reactions involve cleavage of the C 1 -C 2 benzylic bond of radical cation 3 to form the bis-benzylic distonic radical cation 4, which can be trapped either before of after a second oxidative step to form products such as 5.…”

The Phane Properties ofanti-[2.2](1,4)Biphenylenophane

“…For [2.2]paracyclophane bearing 31−33 kcal/mol of strain energy, cleavage of the ethano bridges is thermodynamically favorable due to ring opening and the release of associated strain, leading to benzyl−benzyl biradicals above 200 °C along with substantial chemical reactions, such as isomerization or racemization . In addition, the unusually long ethano bridges made the C−C bonds kinetically labile toward thermal dissociation.…”