Use of intramolecular coulombic interactions to achieve impossible reactions. Photochemical cleavage of 4-nitrophenyl ethers

Photochemical, Electrochemical and Enzymatic Methods for Ether‐Bond Cleavage

“…This situation is reflected in the behavior of alkyl nitrophenyl ether radical anions, which are inert toward any fragmentation. [65][66][67] It is worth noting that cleavage of the alkyl-oxygen bond of alkyl aryl ethers with formation of phenols (dealkylation) is most often observed when alkali metals are used, whereas the aryl-oxygen one is achieved only in particular cases, especially in the presence of potassium and in solvents of low or very low polarity. [68][69][70][71] Similarly, potassium anions cleave exclusively the allyl-oxygen or benzyl-oxygen bond in some glycidyl ethers to give organopotassium compounds as intermediate reaction products.…”

“…The composition of the reaction products and the relationship between the reactivity and the structure of the substrates is consistent with a radical anion mechanism. They used a mercury lamp of moderate pressure (DRL-400, 400 W, 35-40°C) for the photoinitiation and DMSO served as the solvent and found that 4-vinylbenzyl phenyl ether (3), 4-phenylbenzyl phenyl ether (4), and the 1-and 2-naphthylmethyl phenyl ethers (5 and 6, respectively) react with replacement of the phenoxy group. The reactions occur by a radical anion mechanism.…”

“…The photochemical cleavage of phenyl alkyl ethers, especially 4-substituted-phenyl piperidinoalkyl ethers, has been discussed by Marquet. [4,5] It is known that phenyl ethers substituted by electron-attracting groups do not undergo reductive fragmentation. However, related 4-substituted phenyl ethers linked through a methylene chain to a tertiary amine give either alkyl ether photocleavage when the linker between the redox centers is short (two CH 2 groups, 1) or reduction when the linker is long (five CH 2 groups).…”

Electrostatic effects on the photoreactions of nitrophenyl ethers with nucleophiles

“…The "Topologically Controlled Coulombic Interactions (TCCI) Effect" has been introduced and used by us to achieve some previously unknown processes in some cases (i.e reductive cleavage of nitrophenyl alkyl ethers), [1][2][3] and to alter the normal reductive reactivity in others (i.e regioselectivity change in the reductive cleavage of alkyl phenyl ethers). 4,5 This effect involves the altering of the normal behavior of a negatively charged intermediate by specifically placing a positive charge in its structure [i.e.…”

Photocleavage of the C–O bond of 9-phenanthrylmethyl ω-anilinoalkyl ethers via photo-induced intramolecular electron transfer

“…Although the photochemical reactions of compounds with the benzylic carbon-heteroatom bond have been widely in~estigated,~ the cleavage of the C-0 bond of the ethers, especially the aryl CH,O alkyl ethers, on irradiation with Pyrex-filtered light (A =-290 nm) has been rarely observed to date. 4 We now report the photochemical reactions of the ethers 1-3 and the related compounds 4-6 [9-phenanthrylmethyl phenyl ether 4, 9phenanthrylmethyl 3-phenylpropyl ether 5, and 4-(N-methyl-ani1ino)butyl 9-phenanthrylmethyl ether 61.…”