1-methylpyrrolidin-2-imine;hydrochloride

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 6.73 g. (0.05 mole) sample of 2-imino-1-methylpyrrolidine HCl is converted to free base in the usual way. To the K2CO3 -dried, benzene extracts are added a pre-filtered solution of 3,4-dichlorophenylisocyanate (9.4 g.; 0.05 mole). Almost immediately there is a separation of product. After stirring for a short time, the product is collected and recrystallized from acetone-methanol-water and finally from acetone-water to give the pure product, 1-(3,4-dichlorophenyl)-3-(1-methyl-2-pyrrolidylidene)urea. m.p. = 160°-161° C. To the K2CO3 -dried a separation of product the product is collected recrystallized from acetone-methanol-water and finally from acetone-water

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 6.73 g. (0.05 mole) sample of 2-imino-1-methylpyrrolidine HCl is treated with 50 ml. of benzene and 2 ml. of water. With stirring, 10 ml. of 50% sodium hydroxide is added. After stirring about one minute, the benzene layer is decanted onto anhydrous K2CO3 and the extraction repeated twice with 50 ml. portions of benzene. The dried, combined extracts are filtered from the drying agent and the filtrate is treated with 6.66 g. (0.05 mole) of o-tolylisocyanate. After stirring overnight, the mixture is filtered from a small amount of insoluble material and the solvent removed in vacuo. Recrystallization from ethyl acetate and finally from ether gives the pure product, 1-(1-methyl-2-pyrrolidylidene)-3-o-tolyl urea. m.p. = 91°-93° C. After stirring about one minute the benzene layer is decanted onto anhydrous K2CO3 the extraction are filtered from the drying agent the filtrate is treated with 6.66 g After stirring overnight the mixture is filtered from a small amount of insoluble material the solvent removed in vacuo Recrystallization from ethyl acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 6.73 g. (0.05 mole) of 1-methyl-2-iminopyrrolidine HCl is added 1 ml. of water and 50 ml. of benzene. After solution is complete (magnetic stirring), 10 ml. of aqueous sodium hydroxide (50%) is added in one portion. After stirring for about 1 min., the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice. After drying (occasional swirling) the combined benzene extracts are filtered (dicalite) from drying agent and 9.4 g. (0.05 mole) of 2,5-dichlorophenylisocyanate is added to the filtrate in one portion with swirling. After stirring for 3 hours, the solvent is removed in vacuo affording a colorless solid, 1-(2,5-dichlorophenyl)-3-(1-methyl-2-pyrrolidylidene)urea. Recrystallization from acetone (twice) yields the pure product, m.p. = 148.5°-150.5° C. After stirring for about 1 min. the benzene layer is decanted onto anhydrous potassium carbonate The extraction After drying (occasional swirling) the combined benzene extracts are filtered (dicalite) from drying agent and 9.4 g After stirring for 3 hours the solvent is removed in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirring solution of 6.73 g. (0.05 mole) of 1-methyl-2-iminopyrrolidine hydrochloride in about 2 ml. of water is added about 50 ml. of benzene followed by 10 ml. of 50% NaOH. After stirring 1 min. the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice. The combined benzene extracts are filtered from a drying agent (dicalite pad) and rinsed well with dry benzene. To the filtrate is added in one portion with stirring 7.36 g. (0.05 mole) of 2,6-dimethylphenylisocyanate. The reaction mixture is stirred overnight. Solvent removel and recrystallization from ethyl acetate-ether gives the product, 1-(2,6-dimethylphenyl)-3-(1-methyl-2-pyrrolidylidene)urea, as white crystals, m.p. = 119°-120° C. is decanted onto anhydrous potassium carbonate The extraction The combined benzene extracts are filtered from a drying agent (dicalite pad) rinsed well with dry benzene To the filtrate is added in one portion The reaction mixture is stirred overnight Solvent removel and recrystallization from ethyl acetate-ether

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a slurry of 6.73 g (0.05 mole) of 2-imino-1-methylpyrrolidine hydrochloride in 75 ml. of dry benzene is added, with stirring, 2 ml. of water, followed by 6 ml. of 50% NaOH. The benzene is decanted onto anhydrous K2CO3 and the aqueous layer washed twice with 50 ml. portions of benzene, the benzene being collected by decanting onto the K2CO3. The benzene extracts are put under nitrogen and dried for 15 minutes, then filtered rapidly through diatomaceous earth (nitrogen blanket) and washed with 100 ml. of benzene. To the filtrate is added 9.4 g. (0.05 mole) of 2,6-dichlorophenylisocyanate, put under nitrogen, stoppered and stirred at room temperature for 2 hours. The mixture is filtered and the solvent removed under reduced pressure. Trituration of the oily residue results in crystallization, 1-(2,6-dichlorophenyl)-3-(1-methyl-2-pyrrolidylidene)urea, and the white crystals are filtered and collected. After recrystallization from benzene-ether-petroleum ether, the m.p. is 134°-136° C. The benzene is decanted onto anhydrous K2CO3 the aqueous layer washed twice with 50 ml portions of benzene, the benzene being collected by decanting onto the K2CO3 dried for 15 minutes filtered rapidly through diatomaceous earth (nitrogen blanket) washed with 100 ml To the filtrate is added 9.4 g stirred at room temperature for 2 hours The mixture is filtered the solvent removed under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 6.73 g. (0.05 mole) of 1-methyl-2-iminopyrrolidine hydrochloride in 100 ml. of benzene is added 2 ml. of water followed by 5 ml. of 50% NaOH. After stirring for 5 min., the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice with 75 ml. portions of fresh benzene. The combined extracts are filtered from drying agent (dicalite pad and suction). To the filtrate is added in one portion with stirring 6.66 g. (0.05 mole) of p-tolylisocyanate. After stirring for 5 hours, the solution is taken to dryness in vacuo and the resulting solid is recrystallized from ethyl acetate to give 1-(1-methyl-2-pyrrolidylidene)-3-p-tolylurea, m.p. = 136°-137° C. A final recrystallization from acetone shows the product melting at 140°-150° C. Thin layer chromatography (TLC) indicates both samples to be identical in purity. Apparently the two melting points represent polymorphic forms. To a suspension of 6.73 g the benzene layer is decanted onto anhydrous potassium carbonate The extraction The combined extracts are filtered from drying agent (dicalite pad and suction) To the filtrate is added in one portion with stirring 6.66 g After stirring for 5 hours the resulting solid is recrystallized from ethyl acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 6.73 g. (0.05 mole) of 1-methyl-2-iminopyrrolidine hydrochloride in 100 ml. of benzene is added 2 ml. of water followed by 5 ml. of 50% NaOH. After stirring for 5 min., the benzene layer is decanted onto excess anhydrous potassium carbonate. The process is repeated twice with 75 ml. portions of fresh benzene. The combined extracts are filtered rapidly from drying agent (dicalite pad and suction). To the filtrate is added in one portion with stirring 8.21 g. (0.05 mole) of p-nitrophenylisocyanate as a solution in benzene (the isocyanate solution is filtered prior to use). After stirring one hour, the solid, 1-(1-methyl-2-pyrrolidylidene)-3-p-nitrophenylurea, is collected and dried, m.p. = 180°-182° C. Recrystallization from acetone-methanol gives pure product, m.p. = 182°-183° C. To a suspension of 6.73 g the benzene layer is decanted onto excess anhydrous potassium carbonate The combined extracts are filtered rapidly from drying agent (dicalite pad and suction) To the filtrate is added in one portion with stirring 8.21 g After stirring one hour the solid, 1-(1-methyl-2-pyrrolidylidene)-3-p-nitrophenylurea, is collected dried Recrystallization from acetone-methanol gives pure product, m.p. = 182°-183° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 6.73 g. (0.05 mole) sample of 2-imino-1-methylpyrrolidine HCl is converted to free base in the usual way. To the K 2 CO 3 -dried, benzene extracts are added a pre-filtered solution of 3,4 -dichlorophenylisocyanate (9.4 g.; 0.05 mole). Almost immediately there is a separation of product. After stirring for a short time, the product is collected and recrystallized from acetone-methanol-water and finally from acetone-water to give the pure product, 1(3,4-dichlorophenyl)-3-(1-methyl-2-pyrrolidylidene)urea. m.p. = 160°-⪆°C. To the K 2 CO 3 -dried a separation of product the product is collected recrystallized from acetone-methanol-water and finally from acetone-water

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 6.73 g. (0.05 mole) sample of 2-imino-1-methylpyrrolidine HCl is treated with 50 ml. of benzene and 2 ml. of water. With stirring, 10 ml. of 50% sodium hydroxide is added. After stirring about one minute, the benzene layer is decanted onto anhydrous K 2 CO 3 and the extraction repeated twice with 50 ml. portions of benzene. The dried, combined extracts are filtered from the drying agent and the filtrate is treated with 6.66 g. (0.05 mole) of o-tolylisocyanate. After stirring overnight, the mixture is filtered from a small amount of insoluble material and the solvent removed in vacuo. Recrystallization from ethyl acetate and finally from ether gives the pure product, 1-(1-methyl-2-pyrrolidylidene)-3-o-tolyl urea, m.p. = 91°- 93° C. After stirring about one minute the benzene layer is decanted onto anhydrous K 2 CO 3 the extraction are filtered from the drying agent the filtrate is treated with 6.66 g After stirring overnight the mixture is filtered from a small amount of insoluble material the solvent removed in vacuo Recrystallization from ethyl acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 6.73 g. (0.05 mole) of 1-methyl-2-iminopyrrolidine HCl is added 1 ml. of water and 50 ml. of benzene. After solution is complete (magnetic stirring), 10 ml. of aqueous sodium hydroxide (50%) is added in one portion. After stirring for about 1 min., the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice. After drying (occasional swirling) the combined benzene extracts are filtered (dicalite) from drying agent and 9.4 g. (0.05 mole) of 2,5-dichlorophenylisocyanate is added to the filtrate in one portion with swirling. After stirring for 3 hours, the solvent is removed in vacuo affording a colorless solid 1-(2,5-dichlorophenyl)-3-(1-methyl-2-pyrrolidylidene)urea. Recrystallization from acetone (twice) yields the pure product, m.p. = 148.5°-150.5° C. After stirring for about 1 min. the benzene layer is decanted onto anhydrous potassium carbonate The extraction After drying (occasional swirling) the combined benzene extracts are filtered (dicalite) from drying agent and 9.4 g After stirring for 3 hours the solvent is removed in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirring solution of 6.73 g. (0.05 mole) of 1-methyl- 2-iminopyrrolidine hydrochloride in about 2 ml. of water is added about 50 ml. of benzene followed by 10 ml. of 50% NaOH. After stirring 1 min. the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice. The combined benzene extracts are filtered from a drying agent (dicalite pad) and rinsed well with dry benzene. To the filtrate is added in one portion with stirring 7.36 g. (0.05 mole) of 2,6-dimethylphenylisocyanate. The reaction mixture is stirred overnight. Solvent removal and recrystallization from ethyl acetate-ether gives the product, 1-(2,6 -dimethylphenyl)-3-(1-methyl-2-pyrrolidylidene)urea, as white crystals, m.p. = 119°-120° C. is decanted onto anhydrous potassium carbonate The extraction The combined benzene extracts are filtered from a drying agent (dicalite pad) rinsed well with dry benzene To the filtrate is added in one portion The reaction mixture is stirred overnight Solvent removal and recrystallization from ethyl acetate-ether

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 6.73 g. (0.05 mole) of 1 -methyl-2 -iminopyrrolidine hydrochloride in 100 ml. of benzene is added 2 ml. of water followed by 5 ml. of 50 % NaOH. After stirring for 5 min., the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice with 75 ml. portions of fresh benzene. The combined extracts are filtered from drying agent (dicalite pad and suction). To the filtrate is added in one portion with stirring 6.66 g. (0.05 mole) of p-tolylisocyanate. After stirring for 5 hours, the solution is taken to dryness in vacuo and the resulting solid is recrystallized from ethyl acetate to give 1 -(1 -methyl-2 -pyrrolidylidene)-3 -p-tolylurea, m.p. = 136°-137° C. A final recrystallization from acetone shows the product melting at 149°-150° C. Thin layer chromatography (TLC) indicates both samples to be identical in purity. Apparently the two melting points represent polymorphic forms. To a suspension of 6.73 g the benzene layer is decanted onto anhydrous potassium carbonate The extraction The combined extracts are filtered from drying agent (dicalite pad and suction) To the filtrate is added in one portion with stirring 6.66 g After stirring for 5 hours the resulting solid is recrystallized from ethyl acetate