Hydrazide azide

Curtius transformation An alternative to the Hofmann transformation for obtaining an amine from an ester via the hydrazide, azide and isocyanate. Thus ethyl ethanoate is converted into melhylamine by the following series of reactions ... 

Carboxylic acids show most of the standard reactions of benzoic acid. Amides, esters, hydrazides, azides and nitriles can be prepared by standard methods. Thiophenes form stable acid chlorides, furans unstable ones, and A-unsubstituted pyrroles do not form them. 

CARBAMOYLPYRAZINES (AMIDES) AND RELATED COMPOUNDS (HYDRAZIDES, AZIDES, ETC.)... 

Hegarty, Aylward and Scotthave obtained hydrazidic azides (61) by treating hydrzizidic bromides (62) with azide ion in aqueous dioxan (equation 51). As the reactions proceed considerably faster than normal. Sj, processes, these authors postulated the intermediacy of a 1,3-dipolar ion, formed by loss of HBr from the hydrazidic bromide. 

Three groups of these azides are prominent imidoyl azides in which the function C=NX is not part of a ring, those in which it is, and a special class of the former group, hydrazidic azides, containing an open-chain function C=NNRR. ... 

Hydrazides —> Azides. The acid azide method of peptide synthesis, for example of the protected dipeptide (3), has the advantage that no racemization of the peptide vomptments occurs. However, conversion of N-carbobenzoxy-S-benzyl-u-cysteine hydni/.lde (I) into the azide by reaction with nitrous acid under normal conditions (ITor ls considerable amide as by-product (Rt ONHNHNO — RCONH> + fiBaNHaOl. Amide formation can be lUDoraiiad hv onaratlna at hlah aoiditv and... 

Hydrazide— azide. In the synthesis of putrescine dihydrochloride, diethyl adipate is converted into the dihydrazide, which on reaction with nitrous acid affords... 

Curtius, through his studies on diazo esters, discovered successively hydrazine, hydrazides, azides, and hydrazoic acid in 1890 he encountered the rearrangement of acid azides, although he did not reec nize its true nature at the time.i> Since then abundant investigations by Curtius and others have elucidated the reaction and demonstrated its generality. 

Attempts have been made to obtain hydrazide azides by causing di-hydrazides to react with one molecule of nitrous acid. The resulting compounds are unstable, however, and generally undergo intramolecular acylation with elimination of hydrazoic acid and formation of cyclic or polymeric secondary hydrazides. Diphenic dihydrazide is an excep-... 

Starting Material Hydrazide Azide Isocyanate Urethan Amine, etc. 

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