Tetrabutylammonium nitrite

Using the same initial step for the double serial inversion strategy, from methyl glucoside 37, the 2,4-tiiflate intermediates 50 could be produced via a Inflation process (Scheme 15). The 4-triflates of these intermediates were subsequently inversed to the corresponding 4-0-acetyl intermediates 51 by substitution with tetrabutylammonium acetate, followed by inversion of the 2-position by tetrabutylammonium nitrite, to yield a mixture of methyl... 

A mixture of imidazylate 22 (0.055 g, 0.06 mmol) and tetrabutylammonium nitrite (0.483 g, 1.68 mmol) in 2 mL of DMSO was stirred at room temperature. The reaction mixture was diluted with water and extracted with ether. Flash chromatography on silica gel of the residue (petroleum ether—EtOAc, 1 4) afforded 46 (0.022 g, 47%) [a]D +74.0° [Pg.143]

Nitration of naphthalene by use of cerium(IV) ammonium nitrate suspended on silica gel, or in homogeneous solution, in the presence of alcohols, sodium or tetrabutylammonium nitrite and acid gives mainly l-alkoxy-4-nitronaphthalenes together with some of the 2-nitro isomers.34 The results are consistent with initial attack by N02- alone or complexed with cerium(IV) ion at the 1- and 2-positions in a ratio of 5 1. 

More recently another modification for the preparation of peptide azides was introduced by Alfeeva et al-f l using tetrabutylammonium nitrite as auxiliary reagent. In contrast to the alkyl nitrites which are relatively unstable and therefore have to be purified prior to use by distillation, tetrabutylammonium nitrite is a crystalline and stable compound, which is soluble in anhydrous dipolar aprotic solvents. Moreover, in this procedure the acidity of the reaction mixture is adjusted with anhydrous p-toluenesulfonic acid instead of HCl in anhydrous organic solvents. These conditions are experimentally convenient and more easily controlled than those of the Honzl-Rudinger method. Comparative model reactions performed with ferf-butyl nitrite and tetrabutylammonium nitrite produced nearly identical peptide yields. To date, there are no reports of the condensation of larger fragments and peptide cyclization by this azide procedure. 

A copper-catalyzed reaction of ketone 57 with tetrabutylammonium nitrite was reported to afford butyl ester 58 via cleavage of a C-C=0 bond (Eq. (6.12)) [29]. The reaction apparently proceeds through a pathway analogous to the... 

Mellor et al. (1997, 2000) found that when well-dried CAN supported on silica gel, sulfuric acid supported on silica gel, and naphthalene were stirred at room temperature in dichloromethane in presence of tetrabutylammonium nitrite, 1-nitronaphthalene was rapidly... 

Sodium azide-Methyltrioctylammo-nium chloride, 240 Tetrabutylammonium nitrate, 287 of amines Sodium nitrite, 282 Intramolecular reactions 3-Acetoxy-2-tributylstannylmethyl-l-propene, 3... 

These reactions are convenient methods for incorporating a sulfur-containing group onto an aromatic ring. With Ar S, diazosulfides Ar—N=N—S—Ar are intermediates/° which can in some cases be isolated. ° Thiophenols can be made as shown above, but more often the diazonium ion is treated with EtO-CSS or 82, which give the expected products, and these are easily convertible to thiophenols. Aryldiazonium salts are prepared by the reaction of an aniline derivative with an alkyl nitrite (RONO), and when formed in the presence of dimethyl disulfide (MeS-SMe), the product is the thioether, Ar-S-Me. ° Aryl triflates have been converted to the aryl thiol using NaST(P5) and a palladium catalyst, followed by treatment with tetrabutylammonium fluoride ° (see also, 14-22). 

Based on the sodium nitrite and dimethyl sulfate replacement reaction to produce nitromethane, Some [31] used tetrabutylammonium bromide as a catalyst to achieve nucleophilic substitution to improve the conversion. And the obtained purity of nitromethane can be up to 99.9 % with methyl nitrite as the byproduct. The main raw materials are dimethyl sulfate and sodium nitrite with a feeding molar ratio of 1 2, and its synthesis mechanism is ... 

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