Recrystallization trituration

Solid sodium nitrite (0.97 g) was added at room temperature with stirring over a period of one hour to a solution of 2-chloro-9-(2-hydroxyethoxymethyl)adenine (0.5 g) in glacial acetic acid (10 ml). The reaction mixture was stirred for an additional A A hours. The white solid was removed by filtration, washed with cold acetic acid and then well triturated with cold water to remove the sodium acetate present. The solid product was retained. The combined acetic acid filtrate and wash was evaporated at reduced pressure and 40°C bath temperature and the residual oil triturated with cold water. The resulting solid material was combined with the previously isolated solid and the combined solids dried and recrystallized from ethanol to give 2chloro-9-(2-hydroxyethoxymethyl)+iypoxanthine (0.25 g), MP>310°C. Elemental analysis and NMR spectrum were consistent with this structure. 

A mixture of 2chloro5-(2-hydroxyethoxymethyl)+iypoxanthine (0.375 g) and methanol (80 ml) saturated with anhydrous ammonia was heated in a bomb at 125°C for 5 hours. The bomb was cooled in an ice bath and the reaction mixture removed. Solvent and excess ammonia were removed under reduced pressure at 50°C. After the residue was triturated with cold water to remove the ammonium chloride formed, the remaining solid was dried and then recrystallized from methanol to give pure 9-(2-hydroxyethoxymethyl)guanine (0.24 g), MP 256.5°-257°C. 

The residue was acidified with dilute hydrochloric acid and brought to pH 8 with sodium hydroxide and sodium bicarbonate. The mixture was filtered and the filtrate and orange solid were separately extracted with chloroform. The combined, dried, chloroform solutions were evaporated to give 2.2 g of the crude basic triol as an orange solid, when triturated with ether. A portion of the material was recrystallized from ether/light petroleum (BP 40°-60°C) to give a white solid, MP 109°-1irc. 

Aj Preparation of 3-Chloromethyl-6-Chloro-7-Sulfamyl-3,4-Dihydro-Benzothiadizine-1,1-Dioxide—Jo 8 ml of 40-50% chloroacetaldehyde aqueous solution and 7 ml of dimethyl-formamide are added 10 grams of 2,4-disulfamvl-5-chloroaniline. The mixture is heated on a steam bath for 2 hours after which it Is concentrated at reduced pressure. The residue Is triturated with water. The solid material is recrystallized from methanol-ether after-treatment with activated carbon to give 7.2 grams of product, MP 229°-230°C. 

The acetic acid solution was poured into water (100 ml) and extracted with chloroform. The chloroform extracts were washed in turn with water, saturated sodium bicarbonate solution and water, dried and evaporated in vacuo. The residual gum was triturated with ether and a white crystalline solid (1.16 grams) isolated by filtration. Recrystallization from ether (containing a small amount of acetone)-petroleum ether gave 9a-fluoro-110,21-dihydroxy-160-methyl-1 7a-valeryloxypregna-1,4-diene-3,20-dione (871 mg) as fine needles. 

The residue is triturated with methanol to afford a crystalline solid. This material contains no detectable amount of starting material by paperstrip chromatography but shows two UV absorbing spots near the solvent front (methanol-formamide 2 1 vs benzene-n-hexane 1 1). An aliquot is recrystallized three times from a mixture of benzene and n-hexane to give 17a,20,20,21-bis(methylenedioxy)-11(3-hydroxy-6,16a-dimethyl-4,6-pregnadiene-3-one which is used in the subsequent step of the synthesis without further purification. 

Evaporate the dried chloroform solution to a residue, add to the residue 400 ml of liquid ammonia, stir and allow the excess ammonia to evaporate, triturate the residue with hexane to form a crystalline solid, continue trituration with water, and filter the solid to yield substantially pure 2-sulfamyl-4-chloro-nitrobenzene. Recrystallize from aqueous methanol. 

Mix together 4.4 grams of ammonium chloride, 18 ml of methanol, 9 ml of water and 3.0 grams of 2-sulfamyl-4-chloro-nitrobenzene. Heat the mixture to reflux. Add portionwise 4.4 grams of iron filings during a period of about VA hours. Cool the mixture and filter. Concentrate the filtrate to a residue. Triturate the residue with 15 ml of water and filter the solid. Recrystallize the solid from aqueous methanol to yield substantially pure 2-sul-famyl-4-chloroaniline. 

The product separates as a gum from which the supernatant liquid is decanted, and the gum is triturated with 250 cc of water in order to induce crystallization. The crude product thus obtained is recrystallized from 3,200 cc of boiling water and then from 40% aqueous isopropyl alcohol yielding 4,5-dichlorobenzene-1,3-disulfonamide as a white solid, MP 228.5° to 229.0°C. 

The crude reaction product is triturated with ether to give 5.8 grams (85%) of 2,3-di-chloro-4-[2-dimethYlaminomethYl)butyrYl] phenoxyacetic acid hydrochloride in the form of a white solid. After two recrystallizations from a mixture of methanol and ether, the product melts at 165° to 167°C. 

The resultant mixture is evaporated in vacuo and the residue triturated with methylene chloride to afford a crude product. Recrystallization from ethanol-ether (1 3) provides 1 -(2.6-di-chlorobenzylideneamino)-3-hydroxyguanidine hydrochloride MP 173°C to 175°C. When the above process is carried out and S-benzylisothiosemicarbazide hydroiodide is used in place of S-methylisothiosamicarbazide hydroiodide, the identical product is again obtained. 

Methyl bromide (17 grams) was added to a solution of the bis-piperidinodiacetate (4 grams) in methylene chloride (10 ml) and the resulting solution allowed to stand at room temperature for 4 days. The solution was evaporated to dryness, the residue triturated with ether, and filtered to give the bis-methobromide (5.2 grams), MP 206°C. Recrystallization from acetone-methylene chloride gave material MP 214°-217°C. 

To a mixture of 4.4 parts of 4-(2-oxo-1 -benzimidazolinyD-piperidine, 3.3 parts sodium carbonate, a few crystals of potassium iodide in 200 parts 4-methyl-2-pentanone are added por-tionwise 6.2 parts 1 -chloro-4,4-di-(4-fluorophenyl)-butane. After the addition is complete, the whole is stirred and refluxed for 65 hours. After cooling the reaction mixture, there are added 70 parts water. The organic layer is separated, dried over potassium carbonate, filtered and evaporated. The solid residue is triturated in diisopropyl-ether, filtered off again and recrystallized from a mixture of 120 parts acetone and 80 parts 4-methyl-2-pentanone, yielding the crude product. After recrystallization of this crop from 80 parts acetone, 1-(4,4-di-(4-fluorophenyD-butyl] -4-(2-oxo-1 -benzimidazolinyD-piperidine is obtained, melting point 217°Cto2l9°C. 

After being left in the refrigerator overnight the mixture, which has set solid, is triturated with 50 ml of isopropyl alcohol and the solid product filtered off and dried in vacuo over phosphorus pentoxide. 63 g (60% yield) of 1,2-diphenyl-3,5-dioxo-4-n-butyl-4-(N -methylpiper-azinomethyl)pyrazolidine are obtained, melting at 1 29°C after recrystallization from 150 ml of isopropyl alcohol. 

A solution of 200 g of 1 -p-chlorophenvl-2-phenyl-4-(N-pvrrolidino)-butanol-2 in 750 ml of concentrated hydrochloric acid is refluxed for 9 hours thereby causing a dehydration of the butanol compound, and the formation of the hydrochloric acid addition salt of a 1 -p-chloro-phenyl-2-phenyl-4-(N-pyrrolidino)-butene. The hydrochloride salt formed crystallizes in the oily lower layer of the two phase reaction mixture and is removed therefrom by filtration. The filtrate is again refluxed for 9 hours, cooled to0°C,and a second crop of the hydrochloric acid addition salt of the dehydration product is obtained and filtered off. The filtrate containing residual amounts of 1 -p-chlorophenyl-2-phenyl-4-(N-pyrrolidino)-butanol-2 is again refluxed for 9 hours to yield an additional crop of the salt of the dehydration product. The several fractions of the butene compound are combined and triturated with several small portions of hot acetone and recrystallized from alcohol-ether mixture. The hydrochl or ic acid addition salt of the dehydration product, 1 -p-chlorophenyl-2-phenyl-4-(N-pyrrolidino)-butene hydrochloride, melts at about 227°C to 228°C. 

The mixture was cooled in ice and a solution of 2-chloro-3-chloromethy I thiophene (8.8 mmol) in dry tetrahydrofuran was added. The mixture was heated at 70°C for 3 hours and allowed to stir at room temperature overnight. The solvent was removed under vacuum and the residue stirred with dry ether (200 ml). The ether solution was filtered through Celite and saturated with hydrogen chloride gas to precipitate an oil which was solidified by trituration with ether and ethyl acetate. The solid product was collected and recrystallized from a mixture of acetone and diisopropyl ether to give the product, melting point 168°C to 170°C. 

The organic fractions are combined and washed successively with N,N-dimethyl-1,3-propane-diamine, dilute hydrochloric acid, saturated sodium bicarbonate solution and saturated sodium chloride solution. The organic fraction is dried over anhydrous magnesium sulfate. The solvent is then evaporated off. Upon trituration of the residue with methanol, a solid crystallizes, 5-(p-toluovl)-1 -methvlpvrrole-2-acetonitrile, which is removed by filtration and purified by recrystallization from benzene. 

A solution of compound 7 or 8 (100 mmol) in Ph,0/biphenyl (150 mL, 3 1) or in collidine (150mL) was heated under reflux for l-2h. When Ph20/biphenyl was used the reaction mixture was treated with petroleum ether/acetonc (500 mL, 1 1) when collidine was used the solvent was distilled off in vacuo and the residue was triturated with petroleum ether/acetone (100 mL, 1 1). The resulting precipitate was filtered off and recrystallized (2-hydroxyethyl methyl ether/charcoal). 

Tetrachlorodibenzo- -dioxm- C, U.L. 2,7-Dichlorodibenzo-p-dioxin- C, U.L. (0.500 gram) was stirred with 10 ml of chloroform containing trace amounts of FeCls and L and heated to reflux temperature while chlorine gas was passed into the mixture for 18 hours. After cooling, the white insoluble product was collected by filtration and triturated with 15 ml of boiling chloroform. The insoluble portion was transferred to a sublimation flask where it was vacuum-sublimed at 140 °C. The sublimate was recrystallized from 2.5 ml of anisole and washed with chloroform. The product weighed 0.229 gram and contained 2.9 /xCi of radioactivity per mg. 

The residual amine in the filtrate may be isolated in the form of the hydrochloride. The combined solutions are evaporated on a steam bath, 50 ml. of concentrated hydrochloric acid is added, and heating is continued for 2 hours. On cooling, the syrupy solution crystallizes. It is triturated with 50 ml. of ethanol, and the 4-amino-l,2,4-triazole hydrochloride is filtered, washed with a little ethanol, and dried. The yield of the hydrochloride is 10-18 g. (8-15%) the salt melts at 147-148° and may be recrystallized from 95% ethanol, using 10 ml. per gram the melting point is thus raised to 151-152°. 

The validation was performed without any modifications. The procedure is very easy to reproduce and the achieved results correlate with the published material. The yield is somewhat lower than the published result, though monitoring of the reaction by TLC indicated complete consumption of substrate. This is believed to be due to decreased precipitation during recrystallization. Because the product is unstable in solution it is recommended that the recrystallization is performed as quickly as possible. Alternatively, the impurities can be removed by trituration. 

A solution of 7mM of the indolyglyoxamide in 160 ml tetrahydro-furan and 30 ml (30mM) l.OM borane in THF is refluxed 2 hours and cooled. Carefully add water, then evaporate in vacuum and dissolve residue in ether. Wash twice with saturated saline, dry and evaporate in vacuum. Triturate with ether and filter to get the tryptamine-borane in ca. 30% yield. Diss. 200 mg in 2 ml xylene and 2 ml octene-1 and reflux 4 hours. Cool, dilute with hexane and filter to get ca. 80 mg white tryptamine (or dialkyltryptamine) (recrystallize-acetone-hexane etc.). 

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