Azido alcohols chloride

The azido alcohol is dissolved in a minimal amount of dry pyridine and cooled in an ice bath. Methanesulfonyl chloride (1 ml/g of azido alcohol) is added to the cold solution. The reaction mixture is allowed to stand at 0° for 24 to 72 hr. The reaction mixture is processed by pouring into ice water and either filtering the product, if possible, or by extraction with an organic solvent. Methanol or methanol-ether have been used to recrystallize the crude azido mesylates. 

Treatment of the epoxide 32 with sodium azide and ammonium chloride in dimethylformamide gave the azido alcohol 33 which, via the mesylate 34, could... 

Neighbouring group participation by a 5a-azido group is indicated in the conversion of the azido alcohol (26) into the 6ji -chloro derivative (27) by thionyl chloride, again with retention of configuration [i2y]. 

The synthesis begins with the preparation of epoxide 12b fi-om shikimic acid as described in the literature [47]. Nucleophilic ring opening of MOM-protected epoxide 12c with sodium azide in the presence of ammonium chloride generates azido alcohol 12d. The ring opening of the epoxide is... 

Preparations of azide derivatives from styrene-maleic anhydride copolymers, cellulose, and gelatin by attaching aromatic azide compounds are described in the literature. Most of the resultant polymers crosslink rapidly when exposed to light of 260 wavelength. Also, as much as 90% of the hydroxy groups of poly(vinyl alcohol) can be esterified withp-azido-benzoyl chloride. These reactions must be carried out in mixtures of chloroform and aqueous sodium hydroxide. Based on infrared spectroscopy, the following crosslinking mechanism was proposed ... 

Although the Hemetsberger reaction is clearly a powerful synthesis of indole-2-carboxylates, some problems are encountered in addition to the occasional mixture of nitrene cyclization products. Indeed, often the aldoliza-tion route to the 2-azidocinnamates proceeds poorly. This can be obviated at lower temperatures (-30 °C) to stop the reaction at the azido alcohol stage. Subsequent dehydration with thionyl chloride in pyridine or triethylamine afforded the 2-azidocinnamates. This two-step process was superior to the conventional one-step aldolization/ dehydration reaction, as found by Murakami and coworkers [67]. Tercel s group also observed that a low temperature (-78 °C) aldol condensation, isolation of the azido... 

Another synthesis that targeted the Blechert indohzidine (—)-402, reported by Kwon et al., was part of a more comprehensive investigation of asymmetric iodocyclizations catalyzed by Salen complexes, notably the chromium(III) complex R,R)-SSS. In the example of interest, the azido alcohol 559 was transformed into the 2-iodoalkyl tetrahydrofuran 560 in 86% yield and 90% ee when treated with A/-chlorosuccinimide and iodine in the presence of the catalyst (Scheme 75). Reduction of the azide with tin(II) chloride was followed by cyclization under basic conditions and... 

In the presence of alcohols, the corresponding ethers are formed and added nucleophiles such as chloride ion40 or azide ion41 lead to the chloro- and azido-amine products, respectively. Rate constants are independent of the concentration of added nucleophile. Labelled 180 from the solvent is incorporated in the product42. All the evidence points to a reaction mechanism where water is lost from the O-protonated reactant to give a nitrenium ion-iminium ion intermediate which is rapidly trapped by a nucleophile (H2O in this case) to give the final product. This is shown in Scheme 7. Protonation at N- is likely to be more extensive, but there is no pathway to products from the N-protonated intermediate. 

The synthesis of the amino alcohol (5S,6S)-6-amino-5-decanol begins with reaction of the 1-chloropentylboronic ester (Section 1.1.2.1.3.1.) with sodium azide under phase-transfer conditions to form the a-azido boronic ester, which yields the a-chloro- -azidoalkyl boronic ester (1) [yield 92 % 95 % de] with (dichloromethyl)lithium under the usual conditions. The reaction of 1 with butylmagnesium chloride is unusual in that it requires zinc chloride in order to accomplish the replacement of chlorine by butyl to form /J-azidoalkyl boronic ester 2 without boron-azide /1-elimination. Standard peroxidic deboronation and reduction of the azide complete the synthesis15. 

Anisyl Alcohol, Azido—, CgH NjOj and Diaziod—, QH0NsO3 Derivatives were not found in Beil or CA through 1956 Anisyl Alcohol, Nitrates, HjCO QH+ CHa -0N03. Aii three isomers o-, m- and p- were prepd by J.W.Baker T.G.Heggs, Chemistry A. Industry 1954 464 from Ag nitrate and the corresponding chlorides. The p-isomer was too unstable to distil... 

To (-)-ecgonine hydrogen chloride (1.6 mmol) dissolved in 4 ml methyl alcohol was added 40 ml DMF, tetramethylammonium hydroxide (6.4 mmol), and 1-azido-4-iodobutane (8 mmol) and the reaction stirred 12 hours at 50°C. The mixture was concentrated, purified by chromatography with silica gel using EtOAc/methyl alcohol/NH4OH, 9 0.9 0.1, and the product isolated in 78% yield as oil. 

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