Dihydrochloride salt

A mixture of 50 grams of the above prepared piperazine, 30.1 grams of sodium carbonate and 200 ml of benzene is heated to reflux and treated with 39.5 grams of 3-bromopropanol over 1.5 hours. The resulting mixture is refluxed for 2 hours, then filtered, extracted with dilute hydrochloric acid, basified, extracted with benzene, and the extracts are concentrated and distilled to give 1-benzyloxyethyl-4-(3-hydroxypropyl)-piperazine, BP 1BB°to 190°C (0.15 mm). The free base is converted to the dihydrochloride salt by treatment of an alcoholic solution with ethereal hydrogen chloride to separate the salt. 

Thionyl chloride (67 grams) is added over 15 minutes to a mixture of 39.5 grams of the above prepared dihydrochloride salt and 400 ml of chloroform. Refluxing for 4 hours, cooling and filtering yields the dihydrochloride salt of 1-benzyloxyethyl-4-(3-chloropropyl)-piperazine, (VIP 201° to 202°C. The salt in aqueous solution is basified. Extraction with ether and evaporation of the solvent yields the free base. 

A solution of 1.0 gram of 10-[3 -(N-acetoxyethylpiperazinyl)-propyl]-2-trifluoromethyl-phenothiazine in 25 ml of 1 N hydrochloric acid is heated at reflux briefly. Neutralization with dilute sodium carbonate solution and extraction with benzene gives the oily base, 10-[3 -(N-(3-hydroxyethylpiperazinyl)-propyl]-2-trifluoromethylphenothiazine. The base is reacted with an excess of an alcoholic hydrogen chloride solution. Trituration with ether separates crystals of the dihydrochloride salt, MP 224° to 226°C, (from U.S. Patent 3,058,979). 

The viscous oil resin Is slurried twice with 250 cc portions of methanol to remove any unreacted primary amines. The oil residue after being washed with methanol is dissolved in ethyl alcohol and 75 cc of concentrated hydrochloric acid is added dropwise to the warm alcohol solution of the base. The dihydrochloride salts of the several hydroabietyl ethylenediamines precipitates immediately from solution. The salt is then separated by filtering and is washed twice with 100 cc portions of cooled ethyl alcohol. The dihydrochloride salts of the dehy-droabietyl, dihydroabietyl and tetrahydroabietyl ethylenediamine mixture have a melting point of about 292°C to 295°C. On subjecting the mixture to solubility analyses it Is found that the dehydroabietyl ethylenediamine is present in substantially the same proportion as is the dehydroabietylamine in the original "Rosin Amine D."... 

Aminoimidazole (25 R = H), which was generated in situ either by reduction of 4(5)-nitroimidazole (27 R = H) (Section III,A,1) or by hydrolysis of f-butyl-imidazole-4-carbamate (Section III,A,2) was diazotized in situ in tetrafluoroboric acid to give 4-fluoroimidazole (73JA4619, 73JOC3647). Diazotization was also successfully performed on the dihydrochloride salt of 4(5)-aminoimidazole (25 R = H) (87JOC5538). 

Early studies on 4(5)-aminoimidazole (25 R=H) gave a stable urea derivative (37BJ488). Thus, treatment of a solution of 4(5)-aminoimidazole (25 R = H), made slightly acidic by addition of acetic acid, with potassium cyanate gave AMmidazol-4-yl-urea (31) (8%). TV-Imidazol-4-yl-urea (31) was similarly obtained using the dihydrochloride salt of 4(5)-aminoimidazole (25 R = H) (41MI1). 

CAS 35523-89-8 63038-80-2 (Racemic mixture) 220355-66-8 (Diacetate salt) 35554-08-6 (Dihydrochloride salt) 63038-81-3 (Sulfate salt)... 

The Environmental Protection Agency (EPA) has determined that 3,3 -dichlorobenzidine is a probable human carcinogen. The U.S. Department of Health and Human Services (DHHS) has determined that 3,3 -dichlorobenzidine and its dihydrochloride salt may reasonably be expected to be carcinogens. lARC (1987) has determined that 3,3 -dichlorobenzidine is possibly carcinogenic to humans. 

Dichlorobenzidine is commercially produced by reduction of o-nitrochlorobenzene through various reduction procedures to form a hydrazo compoimd, whieh is rearranged in the presenee of mineral acids to form 3,3 -dichlorobenzidine (DCMA 1989 Sax 1987). Commercial supplies are usually provided in the form of the dihydrochloride salt because of its greater stability. 

One company which purchases 3,3 -dichlorobenzidine as the dihydrochloride salt in sealed fiber in drums rinses the empty drums with water, adds the rinse water to the product stream, then sprays the drums with a sodium hypochlorite bleach solution (converting the 3,3 -dichlorobenzidine to a quinone-type compound), and places them in polyethylene bags for disposal (London and Boiano 1986). 

The free base form of 3,3 -dichlorobenzidine is no longer utilized by industry in the United States. It is primarily supplied as the dihydrochloride salt (CPMA 1998). When it was used as the free base, it was handled as a powder or a moist paste (NIOSH 1980). 3,3 -Dichlorobenzidine is not a volatile chemical. 

Acetic anhydride-nitric acid mixtures are extensively used for chloride-catalyzed nitrations. Other nitrating agents have been used and involve similar sources of electropositive chlorine for intermediate chloramine formation. 4,10-Dinitro-4,10-diaza-2,6,8,12-tetraoxaisowurtzitane (TEX) (40), an insensitive high performance explosive (VOD 8665 m/s, d = 1.99 g/cm ), is synthesized by treating the dihydrochloride salt of the corresponding amine (39) with strong mixed acid. ... 

Three products have been observed from the (V-nitration of the dihydrochloride salt of 2,5,7,9-tetraazabicyclo[4.3.0]nonan-8-one (41) with various nitrating agents, and two products observed for the A-nitration of 2,4,6,8-tetraazabicyclo[3.3.0]octan-3-one dihydrochloride (45). Table 5.2 and Table 5.3 give a comparative idea of the efficiency and nitrating power of different nitrating agents. 

The Af-nitration of urea and imide functionality is usually quite difficult compared to the analogous amides. Solutions of dinitrogen pentoxide in nitric acid are frequently employed to synthesize energetic Af, Af -dinitroureas. Yields are often very high and go to completion unlike with many conventional nitrating agents which frequently yield partially nitrated products. Energetic bicycles K-56 (16)" and K-55 (17)" have been prepared from the dihydrochloride salts (14) and (15) respectively. 

The acute LD50 of DCB in rats has been estimated to be 7100mg/kg for the free base and 3800mg/kg for the dihydrochloride salt. Considering these high LD50 values, acute lethality in man after oral exposure is not expected to be very likely. ... 

Synonyms Dihydrochloride salt of diethyl-enediamine piperazidine hydrochloride... 

Ethambutol is a synthetic, water-soluble, heat-stable compound, the dextro-isomer of the structure shown below, dispensed as the dihydrochloride salt. 

BZP is an odorless, colorless, or faint yellow oily liquid at room temperature, and freezes at 32°F (0°C). As it is a strong base, meaning that it has a high pFI, it can cause burns to the skin, lungs, or intestinal tract if consumed in this form. For human or animal consumption, it must be converted to a monohydrochloride or dihydrochloride salt. Most industrial sources supply a BZP preparation that is 97% pure, but they do not disclose what the impurities consist of, and many impurities in industrial chemicals may be toxic or even fatal if consumed. 

Chemical Abstracts Registry No. 86-42-0 (Base) 69-44-3 (Dihydrochloride salt)... 

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