Piperazine hexahydrate

A mixture containing 1.33 g of 5,8-dihydro-8-ethyl-2-methylthio-5-oxopyridol [2,3-d]-pyrimidine-6-carboxylic acid, 1,94 g of piperazine hexahydrate and 20 ml of dimethyl sulfoxide was heated at 110°C for 1 hour with stirring. The separated solid was collected by filtration, washed with ethanol, and then dried at Such a temperature that did not rise above 50°C to give 1,57 g of the trihydrate of the product as nearly colorless needles,... 

Piperazine hexahydrate [142-63-2]" 2844A I(1)371B, N(1)326B TM0850000... 

Fig. 21.15. Regular buckled pattern of pentagons formed by hydrogen-bonded water molecules in pinacol and piperazine hexahydrates and by water and hydroxyl groups in dimethyl hexane- and octanediol tetrahydrates...

The hydrate layer structures which display more regular buckled pentagonal nets belong to two main types. In one, the pentagonal nets consist exclusively of water molecules and are three-dimensionally connected by functional groups of the enclosed molecules. Thus, in piperazine hexahydrate [815], and in pinacol hexa-hydrate [816], the H2N- and HO-groups respectively form hydrogen bonds to the... 

Schwarzenbach D (1968) Structure of piperazine hexahydrate. J Chem Phys 48 4134- 4140... 

A solution of 24.3 g. (0.125 mole) of piperazine hexahydrate in 50 ml. of absolute ethanol, contained in a 250-ml. Erlenmeyer flask, is warmed in a bath at 65° as there is dissolved in the solution, by swirling, 22.1 g. (0.125 mole) of piperazine dihydro-chloride monohydrate (Note 1). As warming in the bath at 65° is continued, there is added during 5 minutes, with vigorous swirling or stirring, 15.8 g. (14.3 ml., 0.125 mole) of recently distilled benzyl chloride. The separation of white needles commences almost immediately. After the solution has been stirred for an additional 25 minutes at 65°, it is cooled, and the unstirred solution is kept in an ice bath for about 30 minutes. The crystals of piperazine dihydrochloride monohydrate are collected by suction filtration, washed with three 10-ml. portions of ice-cold... 

A mixture of cyanomethyl acrylate, piperazine hexahydrate, a little hydroquinone, and ethyl acetate heated 3 hrs. at 70° l,4-bis(cyanomethyl)piperazine. Y 82.7%. F. e. s. R. Harada and Y. Kinoshita, Bull. Chem. Soc. Japan 40, 2706 (1967). 

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