Sodium azide reaction with acid chlorides

Tetrazolium salts have found use as phase transfer catalysts in the oxidation of benzaldehyde640 and toluene193 and the displacement reaction of acid chlorides with sodium azide.639... 

Finally, Lecomte and coworkers reported the synthesis of mikto-arm star-shaped aliphatic polyesters by implementing a strategy based on click chemistry (Fig. 36) [162]. Firstly, the polymerization of sCL was initiated by a diol bearing an alkyne function. The chain-ends were protected from any further undesired reaction by the esterification reaction with acetyl chloride. The alkyne was then reacted with 3-azidopropan-l-ol. The hydroxyl function located at the middle of the chain was then used to initiate the ROP of sCL and y-bromo-s-caprolactone. Finally, pendant bromides were reacted successfully with sodium azide and then with N, N-dimethylprop-2-yn-l-amine to obtain pendant amines. Under acidic conditions, pendant amines were protonated and the polymer turned out to exhibit amphiphilic properties. 

The presence of the propionamide fragment in the stmcture of the anti-inflammatory agent broperamole (125-1) is reminiscent of the heterocycle-based NSAID propionic acids. The activity of this agent may trace back to the acid that would result on hydrolysis of the amide. Tetrazoles are virtually always prepared by reaction of a nitrile with hydrazoic acid or, more commonly, sodium azide in the presence of acid in a reaction very analogous to a 1,3-dipolar cycloaddition. A more recent (and safer) version of the reaction noted later (see losartan, 77-4) uses tributyltin azide. In the case at hand, reaction of the anion of mefa-bromobenzonitrile (125-1) with sodium azide and an acid affords the tetrazole (125-2). Condensation of the anion from that intermediate with ethyl acrylate leads to the product from Michael addition saponiflcation gives the corresponding carboxylic acid (125-3). This is then converted to the acid chloride reaction with piperidine affords broperamole (125-4) [136]. 

The synthesis of a triptan with a chiral side chain begins by reduction of the carboxylic acid in chiral 4-nitrophenylalanine (15-1). The two-step procedure involves conversion of the acid to its ester by the acid chloride by successive reaction with thionyl chloride and then methanol. Treatment of the ester with sodium borohy-dride then afford the alanilol (15-2). Reaction of this last intermediate with phosgene closes the ring to afford the oxazolidone (15-3) the nitro group is then reduced to the aniline (15-4). The newly obtained amine is then converted to the hydrazine (15-5). Reaction of this product with the acetal from 3-chloropropionaldehyde followed by treatment of the hydrazone with acid affords the indole (15-6). The terminal halogen on the side chain is then replaced by an amine by successive displacement by means of sodium azide followed by catalytic reduction of the azide. The newly formed amine is then methylated by reductive alkylation with formaldehyde in the presence of sodium cyanoborohydride to afford zolmitriptan (15-7) [15]. 

A similar procedure was applied to the synthesis of isomeric 1,5-dialkyltetrazoles analogs of the most important naturally occurring fatty acids, from methyl 9(10)-oxooctadecanoate, sodium azide, and titanium(rv) chloride (MeCN, reflux, 5 h) <2003EJ0885>. A convenient synthesis of tetrazoles (e.g., 524) by reaction of trimethylsilyl azide and ZnBr2 with a-dialkylated (3-ketoesters is based on the same approach (Equation 99 Table 32) <2003TL3179>. 

Problem 28.2 Reaction of acid chlorides with sodium azide, NaN3. yields acyl azides RCON3. When heated, these undergo the Curtins rearrangement to amines, RNH2, or, in a non-hydroxylic solvent, to isocyanates, RNCO. Using the structure... 

AZOTURE de SODIUM (French) (26628-22-8) Reacts with hot water. Explosive decomposition in elevated temperatures above 525°F/274°C. Forms ultra-sensitive explosive compounds with heavy metals copper, copper alloys, lead, silver, mercury, carbon disulfide, trifluoroacryloyl fluoride. Violent reaction with acids, forming explosive hydrogen azide. Violent reaction with bromine, barium carbonate, chromyl chloride, dimethyl sulfate, dibro-momalononitrile. Incompatible with caustics, cyanuric chloride, metal oxides, metal sulfides, methyl azide, phosgene. 

A new route to 1,5-disubstituted tetrazoles from the reaction of triphenyliminophosphoranes (156) with acid chlorides and sodium azide (Scheme 17) has recently been developed.375,316... 

Treatment of 51 with an excess of sodium benzoate in DMF resulted in substitution and elimination, to yield the cyclohexene derivative (228, 36%). The yield was low, but 228 was later shown to be a useful compound for synthesis of carba-oligosaccharides. <9-Deacylation of228 and successive benzylidenation and acetylation gave the alkene 229, which was oxidized with a peroxy acid to give a single epoxide (230) in 60% yield. Treatment of 230 with sodium azide and ammonium chloride in aqueous 2-methoxyeth-anol gave the azide (231,55%) as the major product this was converted into a hydroxyvalidamine derivative in the usual manner. On the other hand, an elimination reaction of the methanesulfonate of 231 with DBU in toluene gave the protected precursor (232, 87%) of 203. 

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