Arylcyclopropane photochemistry. Electron-transfer-mediated photochemical addition of methanol to arylcyclopropanes

Triphenylpyrylium Tetrafluoroborate-Sensitized Photochemistry of the Terpenes Sabinene, α-Phellandrene, and α- and γ-Terpinene

“…[23][24][25][26][27] As a result, appropriate donor molecules may undergo a net conversion amounting to ''substitution'' of an activated H atom by a p-cyanophenyl group. With DCB as sensitizer, the geminate radical anion is a poor base as well as a poor hydrogen-atom acceptor; however, it readily undergoes aromatic substitution with loss of cyanide ion.…”

Oxidation of Aryl- and Diarylcyclopropanes in a Pentasil Zeolite: Ring Opening with Deprotonation or Net Hydrogen Migration

“…This reaction typically results in ring-opened products bearing either an alkoxy group (e.g., 6, R ϭ CH 3 ) or an alkoxy and a pcyanophenyl group (e.g., 7); these products are formed by the well-established nucleophilic capture of the corresponding radical cation by the alcohol with ring-opening. [8,9,22,23] In the reaction of trans-1, no isomerization products were observed; apparently nucleophilic capture is faster than isomerization.…”

Triphenylpyrylium Tetrafluoroborate-Sensitized Photochemistry of the Terpenes Sabinene, α-Phellandrene, and α- and γ-Terpinene

“…With DCB as sensitizer, the geminate radical anion is a poor base as well as a poor hydrogen-atom acceptor; however, it readily undergoes aromatic substitution with loss of cyanide ion. [23][24][25][26][27] As a result, appropriate donor molecules may undergo a net conversion amounting to ''substitution'' of an activated H atom by a p-cyanophenyl group. Several examples of such a three-step substitution have been documented.…”

“…Under these conditions the radical cations are scavenged by methanol and the resulting methoxy-substituted free radicals form simple methanol adducts, [14,15] or more complex products by aromatic substitution at the ipso-carbon of the sensitizer radical anion. [23][24][25] Details of the reaction sequence leading to the threecomponent products are particularly well-established for olefins; this reaction is known as the photo-NOCAS reaction (for ''photo-induced nucleophile-olefin-combination-aromatic-substitution''). [24,25] The terpenes studied under these conditions include cyclopropane derivatives (tricyclane), [26] dicyanobenzene (DCB).…”