Pentamethylenediazirine

Submitted by Ernst Schmitz and Roland Ohme 1 Checked by E. J. Corey and Richard Glass 

3-Pentamethylenediaziridine. A solution of 147 g. (1.5 moles) of cyclohexanone in 400 ml. of 15N aqueous ammonia (6.0 moles) in a 1-1. beaker is stirred mechanically and cooled to 0° with an ice-salt mixture. Maintaining the temperature of the solution between 0° and +10°, 124 g. (1.0 mole) of 90% hy-droxylamine-O-sulfonic acid (Note 1) is added in portions of about 1 g. The addition requires about 1 hour, and the mixture is stirred for another hour at 0° and allowed to stand overnight at —15° in a refrigerator. The precipitated crystalline cake is filtered and pressed tight with a glass stopper. The solid is washed with 50-ml. portions of ice-cold ether, toluene, and finally ether. There is obtained 110-115 g. of product which is 70-90% pure (Notes 2 and 3). The product is divided into two portions, each of which is boiled briefly with a 50-ml. portion of toluene the solutions are decanted from small salt residues and cooled to 0° for 2 hours. The precipitates are filtered with suction and washed with 50 ml. of ice-cold petroleum ether. The combined yield of 3,3-pentamethylenediaziridine is 68-78 g. (61-70%), m.p. 104r-107°. The purity is 96-100% (Note 4). 

3-Pentamethylenediazirine. Caution See Note 5. A solution of 34.0 g. (0.2 mole) of silver nitrate in 100 ml. of water is treated dropwise, with shaking, with 100 ml. of 2N sodium hydroxide. The precipitate is filtered with suction and washed 

Hydroxylamine-O-sulfonic acid is prepared according to the method of Gosl and Meuwsen,2 or of Matsuguma and Audrieth.3 The material is available from Eastman Organic Chemicals. 

Analysis of this substance, just prior to use, is carried out in the following manner. A sample is dissolved in water and treated with a solution of potassium iodide in IN sulfuric acid. After 5 minutes the solution is titrated with thiosulfate solution near the end of the titration the solution is boiled to ensure completeness of iodine liberation. Instead of the 90% product, a correspondingly greater amount of the 80% product can be employed. 

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The diazirines are of special interest because of their isomerism with the aliphatic diazo compounds. The diazirines show considerable differences in their properties from the aliphatic diazo compounds, except in their explosive nature. The compounds 3-methyl-3-ethyl-diazirine and 3,3-diethyldiazirine prepared by Paulsen detonated on shock and on heating. Small quantities of 3,3-pentamethylenediazirine (68) can be distilled at normal pressures (bp 109°C). On overheating, explosion followed. 3-n-Propyldiazirine exploded on attempts to distil it a little above room temperature. 3-Methyldiazirine is stable as a gas, but on attempting to condense ca. 100 mg for vapor pressure measurements, it detonated with complete destruction of the apparatus." Diazirine (67) decomposed at once when a sample which had been condensed in dry ice was taken out of the cold trap. Work with the lower molecular weight diazirines in condensed phases should therefore be avoided. 

The diazirines have no basic character, they are not attacked even by strong mineral acids. 3,3-Pentamethylenediazirine (68) could be recovered almost unchanged after the action of methanolic ZN hydrochloric acid for 1 hr. Strong alkalies are also without effect diazirine (67) is unchanged by passing through concentrated sodium hydroxide solution after preparation to eliminate carbon dioxide which is formed simultaneously. ... 

Pentamethylenediazirine, 46, 83 2,4-Pentanedione, alkylation and cleavage with methallyl chlonde and potassium carbonate, 47, 87... 

Diazirine-3,3-dicarboxylic acid, 1080 Difluorodiazirine, 0342 Dipotassium diazirine-3,3-dicarboxylate, 1340 3-Fluoro-3-(trilluoromethyl)-3//-diazirine, 0631 3-Methyldiazirine, 0808 3,3-Pentamethylenediazirine, 2422 Potassium hydrogen diazirine-3,3-dicarboxylate 3-Propyldiazirine, 1594... 

Palladium-on-charcoal in reduction of (-butyl azidoacetate to glycine (-butyl ester, 46, 47 Pelargonyl fluoride, 46, 6 3,3-Pentamethylenediazirine, 46, 83 oxidation to 3,3-dimethyIazarine by silver oxide, 46, 83 Peroxyvanadic acid, 46, 27 Phenanthrene, 9-phenyi, 46, 91 Phenol, 46, 90... 

Pentamethylenediazirine and other diazirines easily add Grignard reagents to the N—N double bond. The reaction leads to N-alkyl diaziridines which can be hydrolyzed to alkyl hydrazines. Cyclohexylhydrazine (85% yield), -propylhydrazine (88%), isopropylhydrazine (95%), and benzylhydrazine were... 

A novel field was opened by Albine and Kisch and by Volpin and co-workersby allowing diazirines to react with metal carbonyls. 3,3-Dimethyl and 3,3-pentamethylenediazirine react with FejlCOjg to form the iron tetracarbonyl derivatives 160 and 161. In acid solution 161 is slowly converted into 162 and 163. 

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