63801-89-8

Upstream product

• 100-66-3 methoxybenzene 
• 63801-86-5 3-(carbomethoxy)-1-(p-nitrophenoxy)pyridinium tetrafluoroborate 
• 96661-30-2 O-(4-nitrophenyl)-N,N-ditosylhydroxylamine 
• 83076-99-7 N-(4'-nitrophenoxy)-4-methylbenzenesulfonamide 

Downstream Products

• 79287-08-4 5-(7-Chloro-1-oxy-quinolin-4-ylamino)-3-diethylaminomethyl-4'-methoxy-biphenyl-2-ol 
• 79287-07-3 5-(7-Chloro-quinolin-4-ylamino)-3-diethylaminomethyl-4'-methoxy-biphenyl-2-ol 
• 111088-11-0 (S)-3-[4-(6,4'-Dimethoxy-biphenyl-3-yloxy)-3,5-dinitro-phenyl]-2-(2,2,2-trifluoro-acetylamino)-propionic acid ethyl ester 
• 111087-84-4 (S)-2-Amino-3-[4-(6,4'-dihydroxy-biphenyl-3-yloxy)-3,5-diiodo-phenyl]-propionic acid; hydrobromide 
• 111088-13-2 (S)-3-[4-(6,4'-Dimethoxy-biphenyl-3-yloxy)-3,5-diiodo-phenyl]-2-(2,2,2-trifluoro-acetylamino)-propionic acid ethyl ester 
• 103594-25-8 4-methoxy-3-(4-methoxyphenyl)phenol 
• 1004457-19-5 2-Benzyloxy-4'-methoxy-5-nitro-biphenyl 

Relevant academic research and scientific papers

PHENOXENIUM IONS. IDENTICAL INTERMEDIATES IN THE ACID-CATALYZED SOLVOLYSIS OF N-TOSYL-O-ARYLHYDROXYLAMINES AND IN THE THERMOLYSIS OF N-ARYLOXYPYRIDINIUM SALTS

The acid-catalyzed solvolysis of N-tosyl-O-arylhydroxylamines in aromatic solvents and the thermolysis of N-aryloxypyridinium salts involve common intermediates, phenoxenium ions, for the formation of hydroxybiphenyl derivatives.Diphenylethers are formed when the heterolysis of the N-O bonds is slow and the aromatic solvent has high nucleophilicity.

Aryloxenium Ions. Generation from N-(Aryloxy)pyridinium Tetrafluoroborates and Reaction with Anisole and Benzonitrile

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).