Hydrazine 1,1-diethyl

In a hood, to a well-stirred suspension of 3.52 gm (0.20 mole) of diethyl-hydrazine-7V,7V -dicarboxylate in 250 ml of water which is maintained at ice temperature with an adequate bath is added, over a 15 min period, 12.3 ml of... 

Br3 CgH2.N N.N(COO.C2H3)NH.COO..C2H3 mw 517.00, N 10.84% ndls (from eth acetate + petr eth), mp explodes 111-15° turns bm on exposure to light sol in ale, eth 81 bena insol in water petr eth decomp in aq NaOH was obtd by reaction of 2,4,6-tribromobenzene-diazonium salt diethyl hydrazine dicar-boxy late in the presence of aq Na acetate 8c Na carbonate (Refs 1 2)... 

Diethylhydrazine 280 A mixture of triethylamine (4 g, 40 mmoles), potassium hydroxide (5.6 g, 100 mmoles), and hydroxylamine-O-sulfonic acid (5.3 g, 47 mmoles) in water (120 ml) is distilled, all the material that distils up to 100° being collected. The content of 1,1-diethyl-hydrazine in the distillate is determined by means of N/40-potassium iodate. The yield is 2.87 g (82 %). The product gives a picrate, m.p. 84°. 

On treatment of l,2-bis(chlorodisulfonyl)ethane with diethyl hydrazine-1,2-dicarboxylate, diethyl l,2,5,6-tetrathio-3,4-diazocane-3,4-dicarboxylate (254) (mp 94-95°C) was isolated in 10% yield (Equation (58)) <71AG(E)407>. Similar reactions took place with l,2-bis(chlorodisulfonyl)benzene to give (255) and (256) ( nation (59)) <74CB771>. 

CeHyONa, Isonicotinic acid hydrazide, 17, 742 CsHsNj, Phenylhydrazine, 33B, 54 CsHjClNj, Phenylhydrazine hydrochloride, 30B, 47 CsHijNjOn, Diethyl hydrazine-1,2-dicarboxylate, 43B, 8 CsHi2N2S4, 3,6-Bis(methylthio)-4,5-diaza-2,7-dithiaocta-3,5-diene, 41B, 76... 

An ethereal soln. of l,2-bis(chlorosulfenyl)ethane added dropwise at 0° during 0.5 hr. with vigorous stirring to diethyl hydrazine-l,2-dicarboxylate and triethylamine in dry ether, and stirred 3 hrs. diethyl 2,3,5,6-tetrahydro-l,4,2,3-dithia-diazine-2,3-dicarboxylate. Y 67%. F. e. s. K.-H. Linke, R. Bimczok. and H. Ling-mann, Ang. Ch. 83, 437 (1971). 

Cinnolines are another relatively unfamiliar class of heterocycle. A synthesis employing tandem C—N bond formations has recently been reported by the Willis research group. Continuing their use of key 2-(2-haloalkenyl)aryl halide substrates, they demonstrated that when combined with diethyl hydrazine-1,2-dicarboxylate, these substrates could undergo tandem copper-catalyzed alkenylation and arylation processes to generate novel diethyl dihydrocinnoline-l,2-dicarboxylates such as 56 [108]. These intermediates could be isolated and then treated with aqueous sodium hydroxide to reveal cinnoline products, such as 57, in moderate to excellent yields as shown in Scheme 24.28. Alternatively, the aromatic products could be revealed by treatment with sodium hydroxide in situ in a one-pot process. 

Peroxyacetic acid added with stirring and ice-salt cooling during 3 hrs. to a soln. of asym. diethyl-hydrazine in 50%-acetic acid, and kept 24 hrs. in the refrigerator tetraethyltetrazene. 

N,N -diethyl-hydrazine N,N-dimethyl-ethane-l,2-diamine N,N -dimethyl-ethane-l,2-diamine 2-(2-amino-ethylamino)-ethanol bis-(2-amino-ethyl)-amine ... 

Heating diethyl 2-phenyl-4,5-thiazoledicarboxylate (16) in alcohol with an excess of hydrazine hydrate gave a mixture of cyclohydrazide (17) and the open-chain 2-phenyl-4,5-thiazoledicarboxylic dihydrazide (18) (Scheme 11) (5). The relative amounts of these two products depended on... 

Thiazolecarboxylic acid hydrazides are prepared by the same general methods used to prepare amides, that is, by treating acids, esters, amides, anhydrides, or acid halides with hydrazine or substitued hydrazines. For example, see Scheme 21 (92). The dihydrazides are obtained in the same way (88). With diethyl 2-chloro-4,5-thiazoledicarboxylate this reaction gives the mono hydr azide monoester of 2-hydrazine-4,5-... 

Hydrazine Alkali metals, ammonia, chlorine, chromates and dichromates, copper salts, fluorine, hydrogen peroxide, metallic oxides, nickel, nitric acid, liquid oxygen, zinc diethyl... 

Phthalic anhydride and diethyl phthalate are easily converted with hydrazine into 4-hydroxyphthalazin-l(2/f)-one. Its substituted derivatives have been prepared using substituted hydrazines, substituted phthalic anhydrides, or diesters or disodium salts of substituted phthalic acids (Scheme 81). However, condensation of phenylhydrazine with phthalic anhydride gives only a small amount of the corresponding phthalazine, the main product being 2-anilinophthalimide. This can be rearranged in the presence of base into the phthalazine derivative. For the preparation of 2,3-disubstituted derivatives, 1,2-disub-stituted hydrazines are reacted with the appropriate phthalic anhydrides or phthaloyl chlorides. Derivatives of 4-amino- or 4-hydrazino-phthalazin-l(2iT)-one have been prepared either from the corresponding monothiophthalimide and 3-aminoisoindolin-3-one (1S4) or from ethyl 2-cyanobenzoate (155) and hydrazine hydrate (Scheme 82). Similarly,... 

Tropolone has been made from 1,2-cycloheptanedione by bromination and reduction, and by reaction with A -bromosuccinimide from cyolo-heptanone by bromination, hydrolysis, and reduction from diethyl pimelate by acyloin condensation and bromination from cyclo-heptatriene by permanganate oxidation from 3,5-dihydroxybenzoic acid by a multistep synthesis from 2,3-dimethoxybenzoic acid by a multistep synthesis from tropone by chlorination and hydrolysis, by amination with hydrazine and hydrolysis, or by photooxidation followed by reduction with thiourea from cyclopentadiene and tetra-fluoroethylene and from cyclopentadiene and dichloroketene. - ... 

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). 

In an initial step triphenylphosphine adds to diethyl azodicarboxylate 5 to give the zwitterionic adduct 6, which is protonated by the carboxylic acid 2 to give intermediate salt 7. The alcohol reacts with 7 to the alkoxyphosphonium salt 8 and the hydrazine derivative 9, and is thus activated for a SN2-reaction ... 

In a scheme intended to produce a more highly substituted oxazolidone, epichlorohydrin is condensed with morpholine in the presence of strong base to give the aminoepoxide, 27. Ring opening of the oxirane by means of hydrazine gives the hydroxy-hydrazine (28). Ring closure with diethyl carbonate leads to the substituted oxazolidone (29). Condensation with 18 affords furaltadone (30). ... 

The reaction mixture is then warmed on the steam bath for an additional two hours (90°C to 95°C). The excess hydrazine hydrate is removed in vacuo. The residue of viscous 1-hy-drazlno-3-morpholinyl-2-propanol Is not distilled, but is mixed with 10.16 g (0.0B6 mol) diethyl carbonate and a solution of 0.3 g sodium metal in 15 ml methyl alcohol. The mixture is refluxed about 2 hours under a 15 cm Widmer column, the alcohol being removed leaving a thick, green liquid residue, which is cooled and the precipitate which forms is removed by filtration and washed well with ether. Yield B2%, MP114°C to 116°C. Recrystallization from isopropanol gives purified 3-amino-5-(N-morpholinyl)-methyl-2-oxazolidone, MP 120°C as the intermediate. 

In recent years, possible alternatives to hydrazine have been suggested, and some have been used on plant. These include carbohydrazide (NH2NHCONHNH2), derivatives of hydroxylamine, e.g. diethyl hydroxy-lamine (HONfCiHjIi), ketoximes, and erythrobic acid (iso corbic acid). These are usually faster scavengers than hydrazine or activated hydrazine . 

Attempts to form a cycloadduct of cyclopent[6]azepine (10) with diethyl diazenedicarboxylate furnished the two isomeric hydrazines 14 and 15, which appear to be the products of direct electrophilic substitution of the cyclopentazepine rather than scission products of the expected [4 + 2] cycloadduct.2... 

The dibenzodiazepines 5 are hydrogenated to the 5,6-dihydro compounds by hydrazine/Raney nickel.149,153 The process is reversed by heating with mercury(II) oxide in diethyl ether.153... 

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