Hydrazine, monohydrate

The reaetion of the propiolie derivatives with hydrazine monohydrate leads to 5-(2-phenylpyrazolo[l,5-a]pyridin-3-yl)-2//-pyrazol-3-ol (Seheme 90) (90EUP379979). 

The beads prepared above (11.58 g.) are suspended in 175 ml. of boiling absolute ethanol, and 0.94 g. (0.0159 mole) of aqueous 85% hydrazine monohydrate is added with stirring. The resulting mixture is refluxed for 10 hours, after which the polymer is collected by filtration and washed with 150-ml. portions of ethanol, aqueous 0.2A sodium hydroxide, distilled water, and anhydrous methanol. After vacuum drying at 60° for four hours, the yield of polymeric benzylamine is 10.38 g. 

Hexanol [111-27-31,42 Hydrazine, monohydrate [7803-57-81,96 Hydrogen peroxide [7722-84-1], 25 Hypochlorous acid, calcium salt [7778-54-3], 118... 

A variety of aromatic diamines have been used for the synthesis of polyimides. It would be too time consuming to report all the pathways described in literature, so here only the most common ones are considered. The biggest part of these different methods leads to nitro compounds generally reduced using H2 or hydrazine monohydrate with catalytic amounts of Pd-C in refluxed ethanol or dioxane. The numbers in parentheses refer to Fig. 5.28 ... 

Poly(arylene ether ketone)s can also be modified by introducing the functional groups using similar approaches to polysulfones. For example, poly(arylene ether ketone)s were sulfonated.189 In addition, o-dibenzoylbenzene moieties in the poly(arylene ether)s can be transformed to heterocycles by cyclization with small molecules. These polymers can react with hydrazine monohydrate in the presence of a mild acid in chlorobenzene or with benzylamine in a basic medium.190 Another example of the use of the o-benzyl cyclization strategy is the intramolecular ring closure of poly(arylene ketone)s containing 2,2/-dibenzoylbiphenyl units to form poly(arylene ether phenanthrenes).191... 

Herbert and Hay reported a bisphenolic monomer, 3,8-bis(4-hydroxyphenyl)-A-phenyl-1,2-naphthalimide (Table 6.1), as well as its corresponding polyf V-phenyl imido aryl ether sulfone) via transimidization reactions with hydrazine monohydrate, aliphatic amines, and an amino acid.193 These polysulfones with... 

For perspective, 1 g of hydrazine monohydrate is equivalent to (TNT) in terms of thermal potential T. Grewer, Thermal Hazards of Chemical Reactions Elsevier Amsterdam, 1994, Vol. 4. 

Important results and a detailed insight into aqueous chemical deposition processes have been reported and discussed elsewhere for CdSe [248, 249] and ZnS [250, 251] target products. We should note also the work of Davies et al. [252] who described an alternative method for the chemical growth of metal sulfides and selenides on the basis of polysulfide or polyselenide solutions (containing hexa- and tetra-chalcogen anions) formed by the dissolution of sulfur or selenium in hydrazine monohydrate. ... 

The 1-isopropoxymethyl derivative of pyrrolo-benzothiazepine 376 can be obtained from aldehyde 375 through the tosyl hydrazone followed by reduction with sodium borohydride in 2-propanol. 1-Methyl substituted 378 is available from aldehyde 375 and hydrazine monohydrate followed by potassium tert-butoxide (Scheme 76, Section 5.1.1 (2004JMC143)). 

The traditional approach to this ring system involves adding hydrazine to [1,2,3]triazole, 5-dialdehyde to condense the fused pyridazine ring <1996CHEC-II(7)489>. Eor example, Trudell and co-workers reported the conversion of dialdehyde 63 into the fused pyridazine ring compound 64 by reaction with hydrazine monohydrate at 50 °C (Scheme 44) <2000JHC1597>. 

Polyethers and polyesters having methoxybenzalazine units with various alkylene groups (C4, C6 and Cg) in the main chain were synthesized from vanillin (7,8). The condensation reaction of 4,4 -alkylenedioxybis (3-methoxybenzaldehyde) [VI] with hydrazine monohydrate was applied to the synthesis of polyethers [VII] (Mn, 7.4 x 103 for C4, 7.3 x 103 for C6 and 4.1 x 103 for Cg derivatives), as shown in Scheme 3. Polyesters [IX] (77jnh, 0.35 dl/g for C4, 0.38 dl/g for C6 and 0.43 dl/g for Cg derivatives) were synthesized from 4,4 -dihydroxy-3,3 -dimethoxybenzalazine [VIII] and di-carboxylic acid chlorides by conventional low temperature solution polycondensation, as shown in Scheme 4. 

In cases where peptides contained either aliphatic hydroxy (Ser or Thr) or carboxy groups (Asp or Glu, or free a-carboxy), a second deformylation procedure was employed 30 To the cyclic peptide analogous to 5 was added hydrazine monohydrate (99%, 5.4 mL, 111 mmol) in EtOH/H20/AcOH (55 35 10, 45 mL) with stirring. The mixture was kept at 37 °C for 16 h after which time completion of the deformylation was verified by analytical RP-HPLC. 

Lehn synthesised guanidinium-based cationic steroids incorporating an acylhy-drazone linker using the approach shown in Fig. 9 [141]. The synthesis was developed from a polyamine scaffold by guanidination of the primary amino groups and alkylation of the secondary amine with methyl chloroacetate to introduce the ester moiety required to form a hydrazide group by reaction with hydrazine monohydrate. Cationic steroid hydrazones were then prepared via an acetic acid catalysed reaction with cholestanones, which demonstrated high transfection efficiency and low toxicity in a variety of cell lines [141]. 

Aminopyridines may be synthesized by conventional nucleophilic displacement of halide substituents. In general, 4-halo substituents are more easily displaced than those at the 2-position. It has been discovered that this order of reactivity is reversed in the presence of a bulky trialkylsilyl group at the 3- or 5-position <20050L127>. For instance, 2,4,6-trifluoro(3-triethylsilyl)pyridine undergoes reaction with hydrazine monohydrate exclusively at the 6-position (Equation 103). 

Hydrazine is marketed as anhydrous hydrazine, as the monohydrate (64% hydrazine), and as a 54.5% aqueous solution (85% hydrazine monohydrate). The largest U.S. producers of hydrazine based on a 2000 report134 are Arch Chemical (23 Million Pounds per Year), Bayer (17 Million Pounds per Year), and Fairmont Chemical (1 Million Pounds per Year). 

Probably the first published structure of an H-bonded super network between amines and alcohols is that of 4-aminophenol (AMPHOL) described by Brown, although in this study the positions of the H-atoms were not unambiguously determined [31]. The crystal structure of hydrazine monohydrate, iS H O, has been reported by Liminga and Olovsson [32], Single crystals suitable for... 

HOMOCONJUGATE ADDITION, 60, 66 Homo-Michael acceptor, 60, 69 Hydrazine hydrate, 61, 17 Hydrazine monohydrate [7803-57-8], 61, 17 HYDROC1NN AM ALDEHYDE, a-METHYL-, 61,82... 

Hydrazine hydrate Hydrazine monohydrate (8, 9) (7803-57-8) 2,2,2-Trichloroethyl chloroformate Formic acid, chloro-, 2,2,2-trichlor-ethyl ester (8) Carbonochloridic acid, 2,2,2-trichloroethyl ester (9) (17341-93-4)... 

Caution Mesitylene is an irritant, potassium cyanide is highly toxic, chlorosultonlc acid is corrosive, hydrazine monohydrate is a toxic, cancer-suspect agent, and dichloromethane is an irritant and should be handled in a well-ventilated hood. 

Using the equipment in Figure 1, but without the HCI gas trap attached, mesitylenesulfonyl chloride (109.7 g, 0.503 mmol, Note 7) is dissolved in 175 mL of dry tetrahydrofuran (THF) and cooled to between -10°C and 0°C in a wet ice-acetone bath. Hydrazine monohydrate (63.0 g, 61.0 mL, 1.26 mol) (Note 3) is dissolved in 30 mL of ice-cold water and added so that the temperature remains below 25°C (Note 10). After the addition is completed, the mixture is stirred for an additional 45 min at room temperature and poured into 250 mL of ice water with stirring. Crude mesitylenesulfonylhydrazine is recovered by suction filtration and then dissolved in 500 mL of dichloromethane. A 150- to 175-mL portion of water separates. The water layer is removed, and the organic layer is washed with one 50-mL portion of ice-cold water, dried over sodium sulfate, filtered, and the solvent is removed on a rotary evaporator. The crystals are triturated in 250 mL of cold hexane, and the fluffy white product (95.4 g, 89%, Note 11) is recovered by suction filtration (Notes 12 and 13). 

Mesitylene (1,3,5-trimethylben2ene), chlorosulfonic acid, hydrazine monohydrate, 2,6-dimethylcyclohexanone and potassium cyanide were purchased from Aldrich Chemical Company, Inc., and used without further purification. 

Summary 5-Aminotetrazole is prepared by reacting hydrazine monohydrate with hydrochloric acid, and calcium cyanamide solution. Afterwards, hydrochloric acid and sodium hydroxide are added, and then the mixture is heated. Afterwards, the mixture is cooled, and upon cooling, the 5-aminotetrazole precipitates. It is then collected by vacuum filtration. Commercial Industrial note For related, or similar information, see Application No. 392,308, February 22, 1995, by Nippon Carbide Kogyo Kabushiki Kaisha, Tokyo, JP, to Masahiro Murotani, Toyama, JP, Hajime Mura, Uozu, JP, Makoto Takeda, Takaoka, JP, and Hiroshi Shibafuchi, Uozu, JP. Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned compound, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned compound for laboratory, educational, or research purposes. 

Pcrhaloalkylpyrazoles 11 have been prepared in excellent yield by the reactions of perhaloal-kylacetylenes 10 with hydrazine monohydrate under mild conditions. ... 

Hydrazine monohydrate (35 mmol) was added to a solution consisting of 3.3.4.4.5.5,6,6,6-nonafluOro-1-phenylhex-l-yne (10a lOmmol) in 95% EtOH (20mL). The resulting mixture was heated to reflux for 2-4 h, then cooled and diluted with HjO (40 mL). The resulting precipitate was collected by filtration... 

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