Hydrazine 1,2-diisopropyl

The hydroxymethyl and carboxyl group of Ser can participate in pyrazole-ring formation, as shown in the transformation of A -protected L-Ser with the Mitsunobu reagent into a /3-lactone which afforded the N-protected serine hydrazide upon treatment with methyl hydrazine. Cyclization to 25 was achieved by diisopropyl azodicarboxylate (DIAD) and TPP [90H(31)79]. 

It was prepd by oxidn of 1,2-diisopropyl-hydrazine-HCI with copper or mercurous oxide in water (Refs 2, 8 10) and is reduced by H colloidal Pd to 1,2-diisopropyl hydrazine. The thermal decompn of azopropane was studied by a number of investigators (Refs 4,5,6,9 11)... 

When K2C03 or CsC03 was used as base in acetonitrile, the desired azetidine was isolated in 85-92% yield. The use of 8equiv of l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as base in dichloromethane at room temperature gave excellent results (90-96%, yield), whereas TEA or diisopropyl ethyl amine (DIEA) gave poor yields (5-25%). Several substituted diazetidines were synthesized (Equation 28). Use of the corresponding optically pure hydrazines 219 afforded chiral diazetidines <2006TL6835>. 

Diisopropyl fluorophosphate Dimethyl sulfate and related compounds Doxorubicin and daunorubicin Drugs containing hydrazine and triazene groups... 

Triazepan l,2-Diisopropyl-5-methyl- E16a, 552 (Hydrazin-1,2-Cycloalkyl.)... 

Sodium hydrazide, R NNIdNa. Mol. wt. 54.04. The reagent is a crystalline yellow solid which explodes at temperatures above 70° or in the presence of oxygen. It is prepared by reaction of sodium amide with anhydrous hydrazine under nitrogen at 0°, for most purposes as a suspension in ether, diisopropyl ether, benzene, or a mixture of these solvents. ... 

In a similar fashion, as carboxylic acids or their esters, certain carboxamides possessing an ortho acyl group tnay also cyclocondense with hydrazine. Thus, Ar,/V-dicthyl-3-(2-pyridy car-bonyl)pyridine-2-carboxamide gives the corresponding pyrido[2,3-(i]pyridazin-H(7//)-one 15 in 89% yield, whereas, in contrast, 3-benzoyl-A, Ar-diisopropylpyridine-2-carboxamide and hydrazine give jV,2V-diisopropyl-5-phenylpyrido[2,3-d]pyridazin-8-amine (16) in 42% yield.50... 

Depending on the relative position of a benzoyl and a Ar,7V-diisopropylcarboxamido group in the 3,4-position of the pyridine ring, heating with hydrazine hydrate in diethylene glycol at 145-200°C produces l-phenylpyrido[3,4-oT]pyridazin-4(3f/)-one (11) or 4-phenylpyrido[3,4-oT]-pyridazin-l(2//)-one (13), respectively. In both reactions minor amounts of (V.jV-diisopropyl-l-phenyl- or -4-phenylpyrido[3,4-[Pg.56]

Hydrazine deriv.. crystals from methanol 4 diisopropyl ether, mp 244-246°. 

Reductive alkylation has occasionally been applied to hydrazine, analogously to that of ammonia, as when acetone and hydrazine in acid solution containing a platinum catalyst at 2 atm hydrogen pressure afforded 1,2-diisopropyl-hydrazine in almost quantitative yield.1014... 

Hydrazination. Isoquinoline allowed to react with 3 moles Na-hydrazide (prepared by adding NaNHg to anhydrous hydrazine under Ng) in anhydrous hydrazine at 20° -> I in diisopropyl ether at 60° 1,1 -... 

Formation of Pyrrolo[3,2-d]pyridazines 2-27 from Pyrrole-2,3-diones 2-24 and Hydrazine Hydrate. A General Procedure for Preparation of 2,4-diisopropyl-3,7-diphenyl- lff-pyrrolo[3,2- f pyridazine (2-27a) In a 20-mL Schlenk tube, hydrazine hydrate (1.0 mmol, 0.057 mL) was added to the ethanol solution (5 mL) of compound 2-24 (180 mg, 0.5 mmol). After the reaction mixture was refluxed for 12 h, the solvent was evaporated in vacuo to give a yellow solid, which was subjected to Si02 column using petroleum ether, ethyl acetate, and triethylamine (100 30 1) as the eluent to give product 2-27a. 

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