Azides benzoyl

Benzoyl azide Biphenyl triozonide Boron tribromide Bromine azide Bromine solutions... 

Acetyl azide, 0771 A-Azidocarbonylazepinc, 2728 Azidocarbonyl fluoride, 0339 Azidocarbonylguanidine, 0820 4-Azidocarbonyl-1,2,3-thiadiazole, 1069 Azidodithioformic acid, 0386 Benzene-l,3-bis(sulfonyl azide), 2210 Benzenesulfinyl azide, 2273 Benzenesulfonyl azide, 2274 Benzoyl azide, 2698... 

Ammonium perchlorate, Impurities, 4004 Azidoacetic acid, 0774 f Aziridine, Acids, 0863 Benzoyl azide, 2698 Benzyl chloroformate, 2931 1,2-Bis(dilluoroamino)-A-nitroethylamine, 0803 Bromine trioxide, 0259 2-Butanone oxime, 1654 2-Butyne-l,4-diol, 1526... 

In general, acyl azides are too unstable to survive at the temperatures required for addition to acetylenes, although benzoyl azide adds readily to ynamines in toluene. Ethoxycarbonyl azide also gives triazoles in good yield with ynamines. The azide adds to propargylic alcohols in boiling ethanol, and to acetylene at 100° under pressure. Addition to phenylacetylene and to electron-deficient acetylenes has been carried out at 130°. Oxazoles are also formed at this temperature by competing thermal decomposition of the azide, and addition of ethoxycarbonylnitrene to the acetylenes. The triazole obtained from phenylacetylene is 2-ethoxycarbonyl-4-phenyltriazole the two 1-ethoxycarbonyltriazoles can be isolated if the addition is carried out at 50° over several weeks. Since the IH- to -triazole isomerization takes place readily in these systems, a IH-structure cannot be assumed for a triazole formed by addition of these azides. 

The acylation of formamidoxime should lead to oxadiazoles unsubstituted in the 3-position. While benzoylation with benzoyl chloride is reported to give dibenzhydroxamic acid 45), 0-acylated formamidoxime could be prepared in good yields with acetic anhydride, the mixed anhydride of acetic and ethyl carbonic acid, benzoic anhydride and benzoyl azide. The cyclization of these esters of formamidoxime into 5-substituted oxadiazoles has been accomplished by heating in an aqueous medium. 

Isocyanate Benzoyl Azide. See 2 Azido-formylphenylisocyanate in Vol 1, p A638-R... 

Preparation. Sodium azide was first prepd in 1891 by Curtius (Ref 1) by saponification of benzoyl azide with an ale or aq soln of NaOH. Wislicenus (Ref 2) prepd NaN, by passing a mixt of NH, and N,0 over molten Na or by treating sodium amide at 150°-250° with nitrous oxide ... 

Azidofor my I phony I isocyanate (2-Isocyanate Benzoyl Azide), OC N-CONj, mw 188.15, N 29.78% Needles (from benz), mp 60° (dec) on careful heating explodes violently on rapid heating or on impact. It can be prepd by heating phthalic acid diazide in benz... 

The photochemical decomposition of acyl azides, on the other hand, proceeds by an intermediate nitrene whicn, in many cases, leads to typical nitrene reaction products. - 1- 111 -14 This is not unreasonable since a photochemical reaction provides enough energy to break the N-N, bond without alkyl or aryl participation. Homer, for example, has proved the existence of benzoylnitrene as the primary cleavage product of the photolysis of benzoyl azide in the presence of trapping reagents (Scheme II).1 7... 

Coleman, Newman, and Garrett have kinetically investigated the decomposition of benzoyl azide in benzene and nitrobenzene solution with halides as Lewis adds.1 7 They grouped the halides into three classes based on the kinetic equation involved ... 

In the presence of gallium chloride, aluminum bromide, aluminum chloride, and ferric chloride, benzoyl azide is decomposed according to eq 2. Here complex formation is very fast, and the decomposition of the complex is the ratedetermining step. The halides do not complex with the phenyl isocyanate formed and, as a consequence, they are not consumed in the reaction. As long as benzoyl azide is in excess, the concentration of the complex is equal to the halide concentration and remains constant. The experimentally determined pseudo-zero-order rate constant depends therefore upon the first power of the initial halide concentration. When, however, the reaction is at a stage where the azide is no longer in excess, the rate of the reaction becomes first order with respect to benzoyl azide and zero order with respect to halide. PhCONj + AlBr, -r - PhCONrAlBr, r+-... 

The halides, GaQs, AlBrs, A1C13, and FeCl3, very probably also exist in dimeric form. With these halides, however, the complexation reaction with the azide is the fast step so that no square-root term is found in the kinetic equation. Arsenic trichloride, arsenic tribromide, phosphorus trichloride, and phosphorus pentachloride were without effect on the rate of decomposition of benzoyl azide. Finally, the authors have observed that the catalytic influence of boron tribromide was much higher than all the other halides. Its rate constant was estimated to be about 18 times larger than that for gallium chloride. 

Some further details about the Curtius reaction with boron halides are given by Fahr and Neumann.1 They have found that benzoyl azide and substituted derivatives react with boron... 

When the triazolinic nucleus carries electron-withdrawing groups at the position, it is far more labile.250 This is attributed to the increased stabilization of the betaine intermediate (53). Thus, triazoline 52 formed by reaction of benzoyl azide with norbornene already decomposes from 40° into N-benzoylaziridine 54.107 This compound isomerizes by distillation under normal pressure quantitatively into an exo-oxazoline derivative (55). 

Benzazide. See Benzoyl Azide under Benzoic Acid... 

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