Hydrazine hydrate in preparation

Hydrazine hydrate, in preparation of sulfonylhydrazides, 40, 93, OS in reduction of 2-nitrofiuorene to 2-aminofluorene, 40, 5 in Wolff-Kishner reduction, 43, 34 Hydrazines, asymmetrically substituted by N-aminatiou of amines by hydroxylamine-O-sulfonic acid, 43,2... 

Girard s reagent T is carbohydrazidomethyltrimethylammonium chloride (I) and is prepared by the reaction of the quaternary ammonium salt formed from ethyl chloroacetate and trimethylamine with hydrazine hydrate in alco-hoUc solution ... 

Girard s reagent P , C5H5NCH2C0NHNH2 C1. In a 1-htre threenecked flask, equipped as in the previous preparation, place 200 ml. of absolute ethyl alcohol, 63 g. (64 -5 ml.) of pure anhydrous pyridine and 98 - 5 g. (84 5 ml.) of ethyl chloroacetate. Heat the mixture under reflux for 2-3 hours until the formation of the quaternary salt is complete acidify a small test-portion with dilute sulphuric acid it should dissolve completely and no odour of ethyl chloroacetate should be apparent. Cool the mixture in ice and salt. Replace the thermometer by a dropping funnel, and add a solution of 40 g. of 100 per cent, hydrazine hydrate in 60 ml. of absolute ethanol all at once. A vigorous exothermic reaction soon develops and is accompanied by vigorous effervescence. The pro duct separates almost immediately. When cold, filter with suction, wash... 

One of the most dramatic developments in the chemistry of N2 during the past 30 years was the discovery by A. D. Allen and C. V. Senoff in 1965 that dinitrogen complexes such as [Ru(NH3)5(N2)1 could readily be prepared from aqueous RUCI3 using hydrazine hydrate in aqueous solution. Since that time virtually all transition metals have been found to give dinitrogen complexes and several hundred such compounds are now characterized.Three general preparative methods are available ... 

Hydrazine hydrate is prepared by treating hydrazine sulfate, N2H4 H2SO4 with sodium hydroxide. The product is collected by distillation under nitrogen. It also is obtained as a by-product in the Bayer Ketazine process for producing hydrazine in which hydrazine solution is hydrolysed under pressure in a ketazine column. 

Pyrazolo[3,4-r-]pyridines have been formed by cyclization of the chloronitrile 155 with hydrazine hydrate in good yield (Equation 56) <2003BML1581>. Townsend and co-workers have reported the preparation of 3-substituted... 

Pyrano[3,4- / pyridazine derivatives 733-735 were prepared by cyclocondensation reactions of 6-aryl-3-(ethoxy-carbonyl, acetyl, or cyano)-2-oxo-2/7,3/7,4/7-pyran-4-carboxylic acids 730-732, respectively, with hydrazine hydrate in boiling ethanol (Equation 61) <2002PS1359>. 

Complex platinous derivatives containing hydrazine are easily prepared by acting upon dichloro-diammino-platinum with hydrazine hydrate in absence of water. The addition of alcohol precipitates diammino-dihydrazino-platinous chloride in colourless prismatic... 

Slowly heat the reaction mixture in a sand bath to 120-125 °C. Do not permit overheating The temperature oj the bath must not exceed 130 °C.) At what temperature does hydrazine hydrate boil Discard the fraction boiling up to 110 °C. Collect the hydrazine hydrate in a preliminarily weighed receiver connected to a cooler via ground-glass joints. Weigh the receiver with the preparation. Calculate the yield. Write the equation of the reaction. 

Hs l -bisfdiphenylpItospMitolediaDelpalladium, ((C6H5)2PCH2CH2P(C6H5)2)2Pd (1). Mol. wt. 1959.36. The reagent is prepared by reduction of PdCl2 with hydrazine hydrate in the presence of the phosphine (DIPHOS). 

Dihydrotetrazolo[5,l-cf][l,5]benzothiazepines (102) were synthesized by nitrous acid treatment of 2,3-dihydro-1,5-benzothiazepin-4-ylhydrazines (101), which were prepared from 2,3-dihydro-l,5-benzothia-zepine-4(5//)-thiones (84) by reaction with hydrazine hydrate in tetrahydrofuran (THF) (Scheme 31) (88JHC1399 89MI2 93F665). The ability of compounds 103 to displace specific [3H]flunitrazepam binding was studied. Only compounds with a chlorine atom at the 9-position were able to interact with [3H]flunitrazepam binding sites (93F665). 

Dioxoosmium(VI) porphyrins were used to prepare dinitrogenosmium(II) porphyrins (path 1, P = OEP, TTP) via reduction with hydrazine hydrate in THF. The latter were transformed into bisalkoxides (path m) by autoxidation in alcohols, in dibromides (path n), thiocarbonyls (path p), nitridoosmium(VI) alkoxides (path q), or osmochromes (path r), respectively. 

Aminoethoxy)methyl]-4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-l,4-dihydropyridine (amlodipine) was prepared from 2-(phthalimidoaminoethoxy)acetoacetate, 2-chlorobenzaldehyde and methyl-3-aminocrotonate under refluxing in ethanol for 24 hours. The ketoester was prepared by the method of Troostwijk and Kellog (JCS Chem. Comm., 1977, p.932). Methyl-3-aminocrotonate can be prepared by known method. Phthalimido-amino-protecting group was removed using hydrazine hydrate in ethanol at the reflux temperature. 

Dihydro-(8//)-5,6-pyridazino[4,5-rf][l,3]oxazin-4-one (153) was prepared from the enamino aldehyde 4-methoxycarbonyl-5-formyl-2,3-dihydro(6//)-1,3-oxazine (152) with hydrazine hydrate in methanol (Equation (20)) <87CCC1773, 87CCC2953). Using the nitrile (154) the resulting pyr-idazinooxazine (155) carries an amino group at position 7 (Equation (21)). 

Dimethylpyrazole has been prepared from acetylacetone and hydrazine hydrate in ethanol3 or hydrazine sulfate in aqueous alkali.4 6 The latter method is preferred, because the reaction with hydrazine hydrate is sometimes violent.3 4 3,5-Dimethyl-pyrazole has also been prepared by hydrolysis and decarboxylation of the 1-carbamido- or 1-carboxamidine derivatives, obtained by reaction of semicarbazide 7 or aminoguanidine 8 with acetylacetone. 

Kumbhar, R S., Sanchez-Yalente, J. and Figueras, F. (1998). Reduction of aromatic nitro compounds with hydrazine hydrate in the presence of iron(III) oxide-MgO catalyst prepared from a Mg-Fe hydrotalcite precursor. Tetrahedron Letts. 39, 2573. 

Palladium Hydrosol or Colloidal Palladium is readily prepared by the reduction of the chloride with acrolein5 or with hydrazine hydrate, in either case in the presence of an extract of Iceland moss 6 or in contact with sodium lysalbinate or protalbinate,7gum acacia,8 or with lanolin9 in a precisely similar manner to platinum,10 the function of the organic additions, which are protective colloids, being to increase the stability of the colloidal phase. 

Osmium Hydrosol or Colloidal Osmium is readily prepared by reducing potassium osmate, K20s04, with hydrazine hydrate in the presence of some protective colloid such as gum acacia 2 or lysalbate (or protalbate) of sodium.3 The reduction may be effected with acrolein 4 if desired. 

Colloidal platinum may also be prepared by reduction of the chloride with hydrazine hydrate, in the presence of a protective colloid vide infra). 

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