78338-71-3Relevant academic research and scientific papers
Photolysis of 4-Methoxyphenyl Aryl Alkylphosphonates
Nakamura, Mitsunobu,Sawasaki, Kouiti,Okamoto, Yoshiki,Takamuku, Setsuo
, p. 141 - 146 (2007/10/02)
UV irradiation of bis(4-methoxyphenyl) methylphosphonate 1a in methanol gave 4,4'-dimethoxybiphenyl 2a as the main product through an intramolecular excimer.With 4-cyanophenyl-4-methoxyphenyl methylphosphonate 1b 4-cyano-4'-methoxybiphenyl 2c and 4-cyano-2-(4'-methoxyphenyl)phenyl methylphosphonate 4b were obtained through an intramolecular exciplex. 3-Cyanophenyl-4-methoxyphenyl methyl phosphonate 1c gave only 3-cyano-4'-methoxybiphenyl 2f.Methyl 4-methoxyphenyl 4-chlorobenzylphosphonate 5a gave dimethyl 4-chlorobenzyl 2-(4'-methoxyphenyl)phosphonate and dimethyl 2-(4'-methoxyphenyl)benzylphosphonate.
Aryloxenium Ions. Generation from N-(Aryloxy)pyridinium Tetrafluoroborates and Reaction with Anisole and Benzonitrile
Abramovitch, Rudolph A.,Alvernhe, Gerard,Bartnik, Romuald,Dassanayake, Nissanke L.,Inbasekaran, Mutiah N.,Kato, Shiego
, p. 4558 - 4565 (2007/10/02)
N-(Aryloxy)pyridinium tetrafluoroborates (4) decompose thermally at 180-200 deg C in anisole and benzonitrile to form products of intermolecular C-O-C and C-C bond formation.With anisole, diphenyl ethers (5) and hydroxybiphenyls (6) are formed; with benzonitrile, the main product is benzoxazole (14).A homolytic process was ruled out by showing that none of these products were formed when perbenzoyl p-nitrophenyl carbonate (18) was decomposed in these solvents.The main products in this case were those of homolytic phenylation (and benzoyloxylation with anisole).A concerted SN2-type heterolytic process was ruled out by showing that the nature of the substituent in the pyridine ring had no effect on the isomer ratios of 5 and 6 in the thermolysis of 4 (X = p-NO2) in anisole.The results are explained in terms of a unimolecular heterolysis of 4 to give the pyridine and aryloxenium ion 2 which now attacks solvent molecules.When an electron-withdrawing substituent is present in 2, more C-O-C than C-C products are formed in anisole.When it is absent only products of C-C bond formation are found.PhO+ is apparently electrophilic enough to attack anisole and give the four possible hydroxymethoxybiphenyls (10-13).
