959957-57-4

Upstream product

• 959957-53-0 N-methanesulfonyl-O-(4-tert-butylphenyl)hydroxylamine 
• 98-54-4 para-tert-butylphenol 

Relevant academic research and scientific papers

Synthesis of Diazoquinones and Azidophenols via Diazo-Transfer Reaction of Phenols

The first efficient diazo-transfer reaction of phenols is described. o-Quinone diazides (diazoquinones) were prepared from phenols in high yields by the diazo-transfer reaction using 2-azido-1,3-bis(2,6-diisopropylphenyl)imidazolium hexafluorophosphate (IPrAP, 2-PF6), which is a safe and stable crystalline. The reaction efficiently proceeded in methanol in the presence of a base. Phenols substituted with electron-donating groups reacted more smoothly than those having electron withdrawing groups. Reactive phenols were diazotized by IPrAP with iPr2NH as a base, and low reactive phenols were diazotized with N,N-dimethyl-4-aminopyridine (DMAP). Furthermore, the formed diazoquinones reacted with sodium azide in 2-methoxyethanol and afforded the corresponding azidophenol in high yields.

Direct Azidation of Phenols

Direct azidation of phenols was developed. By treating chloroimidazolinium chloride 1b and sodium azide with phenol in the presence of a secondary amine in methoxyethanol, ortho-azidation of phenol was achieved.

ELECTROPHILIC AZIDIZING AGENT OR DIAZOTIZING AGENT

PROBLEM TO BE SOLVED: To provide a novel electrophilic azidizing agent that is safe without explosibility, capable of azidizing a nucleophilic compound in an electrophilic manner. SOLUTION: The present invention provides an azide imidazolium derivative re

Chemistry of 4-alkylaryloxenium ion "precursors": Sound and fury signifying something?

(Chemical Equation Presented) Quinol esters 2b, 2c, and 3b and sulfonamide 4c were investigated as possible precursors to 4-alkylaryloxenium ions, reactive intermediates that have not been previously detected. These compounds exhibit a variety of interesting reactions, but with one possible exception, they do not generate oxenium ions. The 4-isopropyl ester 2b predominantly undergoes ordinary acid- and base-catalyzed ester hydrolysis. The 4-tert-butyl ester 2c decomposes under both acidic and neutral conditions to generate tert-butanol and 1-acetyl-1,4-hydroquinone, 8, apparently by an SN1 mechanism. This is also a minor decomposition pathway for 2b, but the mechanism in that case is not likely to be SN1. Decomposition of 2c in the presence of N 3- leads to formation of the explosive 2,3,5,6-tetraazido-1,4-benzoquinone, 14, produced by N3 -induced hydrolysis of 8, followed by a series of oxidations and nucleophilic additions by N3 . No products suggestive of N3--trapping of an oxenium ion were detected. The 4-isopropyl dichloroacetic acid ester 3b reacts with N3- to generate the two adducts 2-azido-4-isopropylphenol, 5b, and 3-azido-4-isopropylphenol, 11b. Although 5b is the expected product of N3- trapping of the oxenium ion, kinetic analysis shows that it is produced by a kinetically bimolecular reaction of N3- with 3b. No oxenium ion is involved. The sulfonamide 4c predominantly undergoes a rearrangement reaction under acidic and neutral conditions, but a minor component of the reaction yields 4-tert-butylcresol, 17, and 2-azido-4-tert-butylphenol, 5c, in the presence of N3-. These products may indicate that 4c generates the oxenium ion 1c, but they are generated in very low yields (ca. 10%) so it is not possible to definitively conclude that 1c has been produced. If 1c has been generated, the N3--trapping data indicate that it is a very short-lived and reactive species in H2O. Comparisons with similarly reactive nitrenium ions indicate that the lifetime of 1c is ca. 20-200 ps if it is generated, so it must react by a preassociation process. Density functional theory calculations at the B3LYP/6-31G*//HF/6-31G* level coupled with kinetic correlations also indicate that the aqueous solution lifetimes of 1a-c are in the picosecond range.