Hydrazine production from

Dissolve 10 g. of chloro- 2,4-dinitrobenzenet in 50 ml. of dioxan in a 250 ml. conical flask. Dilute 8 ml. of hydrazine hydrate with an equal volume of water and add this slowly with shaking to the dioxan solution, keeping the temperature between zo " and 25°. Heat under reflux for 10 minutes to complete the reaction and then add 5 ml. of ethanol and heat again for 5 minutes. Cool and filter oflF the orange 2,4-dinitrophenylhydra-zine. Recrystallise the dry product from ethyl acetate m.p. 200° (decomp.). Yield, 7 g. 

In a recent review of heterocyclic compounds no further mention is made of the three-membered ring structures for the condensation products from hydrazine and carbonyl compounds. However, the products obtained from azodicarbonyl derivatives with aliphatic diazo compounds were formulated as diaziridines [Eq. (1)]. Recent investi-... 

Similar selectivity in displacement reactions is shown by 3,6-dichloropyridazine (153) (available by halogenation of the product from maleic anhydride and hydrazine). Thus, reaction of the dihalide with the sodium salt from sulfanilamide (93) affords fiulfachloropyridazine (104). Reaction of this last with sodium methoxide under somewhat more drastic conditions results in displacement of the remaining chlorine to give sulfamethoxypyrida-zine (105). ... 

Synthesis gas is a major source of hydrogen, which is used for producing ammonia. Ammonia is the host of many chemicals such as urea, ammonium nitrate, and hydrazine. Carbon dioxide, a by-product from synthesis gas, reacts with ammonia to produce urea. 

The rate of the reaction is influenced by the speed of stirring. At slow speeds, 30 hours may be required for completion, without, however, any lowering of the final yield. The role of pentane is to continuously remove newly formed product from the hydrazine solvent. 

In contrast with the molybdenum enzyme, hydrazine (N2H4) is a minor product from the reduction of N2 by vanadium nitrogenase (186). The production of N2H4 increases with increasing temperature up to 50°C, at which temperature the ability of vanadium nitrogenase to produce to NH3 ceases, although the production of N2H4 increases... 

BW-755C and its congeners can be considered as reducing agents either because they are dihydroaromatic compounds, or because of the presence of a hydrazine moiety, which is easily oxidized. In the latter vein, the amid-razone CBS-1114 (100) inhibited platelet CO and 12-LO, the release of 5-LO products from human or rabbit neutrophils (1-10 /M), and leukocyte... 

Moderate to good enantioselectivities were obtained for nearly all examples, but the products from 83a-c could be recrystallized to higher enantiomeric purity. Addition of iodine was critical for catalysis as was the use of a ligand with electron-poor para-fluorophenyl groups on the phosphorous atom. Substitution at the 3 position of the pyridine ring was described as being difficult for both the quinolines and pyridine systems. The resulting hydrazine derivatives could be easily converted to piperdines by reduction with Raney nickel or under Birch conditions. 

Treatment of the bis(pyrazoyl)tetrazine (197) with an excess of hydrazine hydrate generates 3,6-bis(hydrazino)-l,2,4,5-tetrazine (208), a compound which might find use as an energetic additive in high performance propellants. Several salts of (208) have been reported, including the dinitrate and diperchlorate. 3,6-Dichloro-l,2,4,5-tetrazine (209), the product from treating (208) with chlorine in acetonitrile, reacts with the sodium salt of 5-aminotetrazole (210) to yield (211) (C4H4N14 - 79 % N). ... 

Isocyanates and isothiocyanates are reduced to methylamines on treatment with LiAlH4. LiAIH4 does not usually reduce azo compounds622 (indeed these are the products from LiAIH4 reduction of nitro compounds, 9-67), but these can be reduced to hydrazo compounds by catalytic hydrogenation or with diimide623 (see 5-9). Diazonium salts are reduced to hydrazines by sodium sulfite. This reaction probably has a nucleophilic mechanism.624... 

Only one unrefuted synthesis of this ring system has been reported in the literature (76MIP21700). A mixture of (142) and the desired ring system (143) are reported as the products from the reaction of the anhydride (141) with an excess of hydrazine hydrate in water at reflux temperature for 3.5 hours. If the reaction is carried out using equimolar amounts of the starting anhydride and hydrazine hydrate in aqueous ethanol for 5 days, the formation of the pyridazinone (144) is reported. 

Dinitro-2,2 -azoxynapbthalene, yellowish brn-red iridescent ndls (from nitrobenzene), mp 305-6° 315° insol in w, ale. ether, benz or glacial acetic acid. This compd was obtd as one of the products from the reaction of hydrazine or hydrazine hydrate and 4-chloro-l,3-dinitronaphthaline in ale... 

Cognate preparation. 2-Phenylethylamine. Prepare 2-phenylethylphthali-mide as above by substituting 2-phenylethyl bromide (Expt 5.55) for benzyl chloride recrystallise the crude product from glacial acetic acid m.p. 131— 132°C. Convert it into 2-phenylethylamine by treatment with hydrazine hydrate and hydrochloric acid as described for benzylamine. The yield of 2-phenylethylamine, b.p. 200-205 °C, is about 95 per cent. 

A nitrene generated from the reaction of A-aminophthalimide (101) and PhI(OAc)2 was key to the metal-free ring expansion of alkylidenecyclopropanes (102) and an alkylidenecyclobutane.85 The authors propose two plausible mechanisms for these ring-expansion reactions either an aziridine is formed which undergoes facile rearrangement to form the final 2,2-disubstituted cyclobutylidene hydrazine product (103), or reaction of the alkylidenecyclopropane with the nitrene generates an ionic or diradical species which rearranges. 

The scope aromatic C-N bond formation extends beyond simple amine substrates. For example, selected imines, sulfoximines, hydrazines, lactams, azoles, and carbamates give useful products from intermolecular aromatic C-N bond formation. Intramolecular formation of aryl amides has been reported. In addition, allylamine undergoes arylation, providing a readily cleaved amine alternative to the ammonia surrogates benzylamine, t-butylcarbamate, or benzophenone imine. Although it is an amine substrate, the reaction of this reagent is included here because of its special purpose. 

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