Amines hydrazides

Besides primary amines, hydrazides or hydrazines also react with cyclopropanone to afford the appropriate adducts. The reaction of frfln.s-2,3-di-terr-butylcyclopropanone (34) with tosyl-hydrtizine afforded the 1 1 adduct 35, which underwent dehydration to provide the corresponding tosylhydrazone 36 upon heating at 80 °C in vacuo (0.1 Torr) for 10 h. ... 

The poly(amine-hydrazide)s can be prepared from the polycondensation of 9-[MA -di(4-carboxyphenyl)amino]anthracene with terephthalic dihydrazide and isophthaUc dihydrazide by the Yamazaki phosphorylation reaction. The poly(amine-hydrazide)s are readily soluble in many common organic solvents and can he solution cast into transparent films [48]. The materials can be thermally cyclodehydrated into the corresponding oxadiazole polymers in the range of 300-400 °C. An anthrylamine-based poly(amine-1,3,4-oxadiazole)s shows electrochromic characteristics with changing color from the pale yellow neutral form to the red in the range of 0.00 to -2.20 V. 

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 ... 

The independent preparation of potassium phthabmide (from a solution of phthalimide in absolute ethanol and potassium hydroxide in 75 per cent, ethanol) may be avoided in many cases by boiling phthalimide with the halide in the presence of anhydrous potassium carbonate. The N-substituted phthalimide (I) is frequently cleav with difficulty this is often facilitated by reaction with hydrazine hydrate to give an intermediate product, which is easily decomposed by hydrochloric acid to 3deld the insoluble hydrazide of phthaUc acid (II) and the primary amine (III) ... 

A special problem arises in the preparation of secondary amines. These compounds are highly nucleophilic, and alkylation of an amine with alkyl halides cannot be expected to stop at any specifle stage. Secondary amides, however, can be monoalkylated and lydrolyzed or be reduced to secondary amines (p. 11 If.). In the elegant synthesis of phenyl- phrine an intermediate -hydroxy isocyanate (from a hydrazide and nitrous acid) cyclizes to pve an oxazolidinone which is monomethylated. Treatment with strong acid cleaves the cyclic irethan. 

The aminolysis of esters of pyrimidine occurs normally to yield amides. The reagent is commonly alcoholic ammonia or alcoholic amine, usually at room temperature for 20-24 hours, but occasionally under refiux aqueous amine or even undiluted amine are used sometimes. The process is exemplified in the conversion of methyl pyrimidine-5-carboxylate (193 R = Me) or its 4-isomer by methanolic ammonia at 25 °C into the amide (196) or pyrimidine-4-carboxamide, respectively (60MI21300), and in the butylaminolysis of butyl ttracil-6-carboxylate (butyl orotate) by ethanolic butylamine to give A-butyluracil-5-carboxamide (187) (60JOC1950). Hydrazides are made similarly from esters with ethanolic hydrazine hydrate. 

The reactions of amides fall into hydrolysis, dehydration and degradation (to amines) acid hydrazides and acid azides undergo additional reactions. 

Degradation of acid hydrazides or acyl azides to amine or amine derivatives. 

Classically, amides and hydrazides have been prepared from an ester or an acid chloride and an amine or hydrazine, respectively they can also be prepared directly from the acid as shown in eqs. 1-3. 

The Cunius degradation of acyl azides prepared either by treatment of acyl halides with sodium azide or trimethylsilyl azide [47] or by treatment of acyl hydrazides with nitrous acid [f J yields pnmarily alkyl isocyanates, which can be isolated when the reaction is earned out in aptotic solvents If alcohols are used as solvents, urethanes are formed Hydrolysis of the isocyanates and the urethanes yields primary amines. 

It should be noted that furoxan amides and hydrazides could only be prepared in aqueous solution. In ether solution, reaction of diethyl furoxandicarboxylate with amines and hydrazine derivatives have been shown to give isoxazolones 93 (Scheme 45) (08CB3512, 09LA52, 09LA80). 

Hydrazides of vicinal acetylene-substituted derivatives of benzoic and azole carboxylic acids are important intermediate compounds because they can be used for cyclization via both a- and /3-carbon atoms of a multiple bond involving both amine and amide nitrogen atoms (Scheme 131). Besides, the hydrazides of aromatic and heteroaromatic acids are convenient substrates for testing the proposed easy formation of a five-membered ring condensed with a benzene nucleus and the six-membered one condensed with five-membered azoles. 

The A-substituted derivatives of 4-oxo-4//-pyrido[l,2-n]pyrimidine-3-carboxamides and -3-acetamides and l,6-dimethyl-4-oxo-1,6,7,8-tetrahy-dro-4//-pyrido[l,2-n]pyrimidine-3-carboxamide were prepared by treatment of the appropriate 3-carboxylic acids and acetic acid, first with an alkyl chloroformate in the presence ofNEt3 in CHCI3 below — 10°C, then with an amine (98ACH515). A-Phenethyl and A-[2-(3,4-dimethoxyphenyl)ethyl] derivatives of 6-methyl-6,7,8,9-tetrahydro-4//-pyrido[l, 2-n]pyrimidine-3-acetamide were obtained in the reaction of 6-methyl-6,7,8,9-tetrahydro-4//-pyrido[l,2-n]pyrimidine-3-acetic acid and phenethylamines in boiling xylene under a H2O separator. Hydrazides of 4-oxo-4//- and 4-oxo-6,7,8,9-tetrahydro-4//-pyrido[l, 2-n]pyrimidine-3-acetic acid were prepared from the appropriate ester with H2NNH2 H2O in EtOH. Heating 4-oxo-4//- and 6-methyl-4-oxo-6,7,8,9-tetrahydro-4//-pyrido[l, 2-n]pyrimidine-3-acetic hydrazides in EtOH in the presence of excess Raney Ni afforded fhe appropriafe 4-oxo-6,7,8,9-fefrahydro-4//-pyrido[l,2-n]pyrimidine-3-acefa-mide. In the case of the 4-oxo-4// derivative, in addition to N-N bond... 

The hydrolytic cleavage is usually slow, and requires drastic reaction conditions. A more elegant method is presented by the Ing-Manske procedure, where the A-alkylated imide is treated with hydrazine under milder conditions. In addition to the desired amine 5, the cyclic phthalic hydrazide 6 is then formed ... 

The methyl ester 2 can be converted into the trithiatriazepinamine 12 via the hydrazide 9. Nitrosation gives the azide 10. which undergoes a Curtius rearrangement to the isocyanate 11, which is not isolated but hydrolyzed in situ to the amine 12.418... 

As in 10-55 hydrazides and hydroxamic acids can be prepared from carboxylic esters, with hydrazine and hydroxylamine, respectively. Both hydrazine and hydroxylamine react more rapidly than ammonia or primary amines (the alpha effect, p. 445). Imidates, RC(=NH)OR, give amidines, RC(=NH)NH2. Lactones, when treated with ammonia or primary amines, give lactams. Lactams are also produced from y- and 5-amino esters in an internal example of this reaction. 

Analogous reactions have been carried out with hydrazide ions (R2NNH A mixture of NO2 and O3, with excess NaHS03, converted pyridine to 3-aminopyri-dine. ° For other methods of aminating aromatic rings, see 11-6. 

Among the agricultural chemicals used for the cultivation of tobacco crops we find several amines, amides and carbamates. These include dimethyldodecylamine acetate (Penar), maleic hydra-zide-diethanolamine (MH-30), and carbaryl (Sevin) as a representative of the methyl urethanes (Figure 3 , 14), It is known that small quantities of these agents are found as residues in harvested tobacco (15). To date, only diethanolamine (DELA), the water-solubilizer for maleic hydrazide in MH-30, has been studied as a possible precursor for nitrosamines in tobacco and in tobacco smoke. In 1976, more than 1,400 metric tons of maleic hydrazide had been used on U.S. tobacco (16), most of which had been applied as the MH-30 formulation with diethanolamine (14,16). 

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