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Cyanogen azide

The photolytic and thermolytic decomposition of azides in the presence of olefins has been applied to aziridine synthesis. However, only a limited number of steroid aziridines have been prepared in this manner. The patent literature reports the use of cyanogen azide at ca. 50° for 24 hours in ethyl acetate for the preparation of an A-nor- and a B-norsteroidal aziridine. The addition is believed to proceed via a triazoline. The reaction of cholest-2-ene with ethyl azidoformate takes place in a nonselective manner to produce a mixture of substances, including C—H insertion products. [Pg.30]

A solution of 5 g (14 mmoles) of 5a-cholest-2-ene in 100 ml ethyl acetate and 8 ml of 2.8 M (22 mmoles) cyanogen azide (CAUTION See Chapter 15 and ref. 139b) in ethyl acetate is heated at 50-53° for 24 hr, during which time about 22 mmoles of nitrogen is evolved. Solvent is removed by evaporation and the residue is applied in benzene to a column of 160 g of neutral alumina (activity grade III). Elution with petroleum ether-benzene (1 1) gives 1.6 g of... [Pg.36]

C. Reaction of Enamines of 3-Ketones with Cyanogen Azide... [Pg.412]

Cyanogen azide is a useful reagent for conversion of pyrrolidine enamines of 3-keto steroids to A-norsteroids. " Ring contractions can be carried out in the presence of 17j5-hydroxy, 17j -acetoxy, 20-keto groups and isolated double bonds. In a typical procedure, 17j -hydroxy-5a-androstan-3-one (partial formula 8) is converted into the enamine (9) by pyrrolidine in benzene... [Pg.412]

The cyanogen azide-enamine ring contraction procedure has also been used to prepare an A-dinorsteroid (16) from 17j5-acetoxy-A-norandrostan-2-one (15). " ... [Pg.413]

The methyl ester (100, R = CH3), derived from this A-nor acid by treatment with diazomethane, is different from the ester (102) obtained either by Favorskii rearrangement of 2a-bromo-5a-cholestan-3-one (101) or by the action of cyanogen azide on 3-methoxy-5a-cholest-2-ene (103) followed by hydrolysis on alumina. The ketene intermediate involved in photolysis of (99) is expected to be hydrated from the less hindered a-side of the molecule to give the 2j -carboxylic acid. The reactions which afford (102) would be expected to afford the 2a-epimer. These configurational assignments are confirmed by deuteriochloroform-benzene solvent shifts in the NMR spectra of esters (100) and (102). ... [Pg.441]

The reaction of cyanogen azide with enamines of cyclic ketones to yield a cyanoamidine with one less member in the carbocyclic ring represents a potentially valuable method of ring contraction under mild conditions (199a). The reaction probably proceeds first by 1,3 cycloaddition of the azide to the enamine followed by rearrangement and elimination of a molecule of nitrogen. [Pg.245]

Extensions of 1,3-dipolar additions of aromatic azides (720,721) to other enamines (636), and particularly to the enamine tautomer of SchilTs bases, were explored (722,723). Further nitrone additions were reported (724,725) and a double nitrile oxide added to an endiamine (647). Cyanogen azide and enamines gave cyanoamidines through rearrangement (726). [Pg.445]

Similarly, the regiospecific 1,3-dipolar cycloaddition reaction of 1-methyl-1,2-dihydropyridines 41 with cyanogen azide (50a) and selected organic azides 50c and 50g afforded 2-methyl-2,7-diazabicyclo[4.1.0]hept-4-enes 57, which can be elaborated to 1-methyl-l,2,5,6-tetrahydropyridylidene-2-cyanamide (58) and 1-methyl-2-piperidylidenes 59a-d (85CJC2362). [Pg.279]

The solid explodes when mechanically shocked or heated in a closed vessel [1], Preparative methods are hazardous because of the need to heat the explosive precursor, cyanogen azide [1,2]. [Pg.371]

This explosive solid may be produced during preparation of cyanogen azide. [Pg.374]

A reaction that produces NCN3, known as cyanogen azide, is... [Pg.135]

BrCN + NaN3 > NaBr + NCN3 (cyanogen azide)... [Pg.135]

Draw the structure of cyanogen azide. Speculate on the stability of this molecule. [Pg.135]

Milligan and Jacox 44 have recently reported an elegant synthesis of CF2 in an argon matrix. Carbon atoms, produced from the photolysis of cyanogen azide, were allowed to react with molecular fluorine, and the presence of CF2 was demonstrated from infrared spectra. Use of radiation effective in photolyzing F2 produced CF3 from the reaction of the CF2 with atomic fluorine. [Pg.12]

Bromine azide, 0256 Chlorine azide, 4030 Cyanogen azide, 0544 Fluorine azide, 4307 Iodine azide, 4621 See metal pnictides... [Pg.182]

Cyanogen azide is less stable than most azides, and few additions have been attempted. Addition to acetylene and to alkynesgives the triazoles, which, like some sulfonyltriazoles, exist in equilibrium with open-chain tautomers. [Pg.40]


See other pages where Cyanogen azide is mentioned: [Pg.619]    [Pg.792]    [Pg.359]    [Pg.30]    [Pg.412]    [Pg.413]    [Pg.414]    [Pg.414]    [Pg.414]    [Pg.415]    [Pg.454]    [Pg.457]    [Pg.279]    [Pg.143]    [Pg.27]    [Pg.157]    [Pg.213]    [Pg.213]    [Pg.1607]    [Pg.1607]    [Pg.888]    [Pg.129]    [Pg.138]    [Pg.35]    [Pg.40]    [Pg.82]    [Pg.279]   
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See also in sourсe #XX -- [ Pg.173 , Pg.883 ]

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See also in sourсe #XX -- [ Pg.280 ]

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Cyanogen

Cyanogen azide decomposition

Cyanogen azide formation of cyanonitrene

Cyanogen azide reactions with alkenes

Cyanogen azide, cycloaddition reactions

Cyanogen azide, photolysis

Cyanogene

Cyanogenic

Nitrenes, cyanosynthesis via decomposition of cyanogen azide

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