2-bromopentane

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Sodium ethoxide was prepared from sodium metal (7.61 g) and absolute ethanol (200 ml). Diethyl malonate (50.3 ml) was added dropwise to the ethanol containing sodium ethoxide. After heating to 80° C., 2-bromopentane (50 g) was added and the mixture was reflued for 24 h. Diethyl (2-pentyl)malonate (62.7 g) was obtained after the usual work-up. Diethyl (2-pentyl)malonate was added to a 50% potassium hydroxide solution and the mixture was heated for 3 h while water/ethanol being distilled off. After cooling, the solution was acidified with concentrated hydrochloric acid. Then, the solution was extracted with ethyl acetate. The extract was concentrated under reduced pressure, and the resulting product was heated to 180° C. until bubbling ceased. After distillation, colorless 3R,S-methy-caproic acid was obtained. Yield : 27.7 g (35%), b.p. 200° C./760 mmHg.

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

Procedure: To a solution of 1.1 g of dl-5-chloro-6-ethyl-4-(α-ethyl-4-hydroxybenzyl)aminopyrimidine.sodium salt dissolved in 30 ml of N,N-dimethylformamide was added 0.6 g of 2-bromopentane, and the mixture was stirred at 90° to 100° C. for 8 hours. After completion of the reaction, the reaction mixture was poured into water and separated oily product was extracted with ethyl acetate. The extract was washed with water, dried over anhydrous sodium sulfate and ethyl acetate was distilled off under reduced pressure. The oily product obtained was isolated by column chromatography (Wako Gel C-200, trade name, eluted with toluene:ethyl acetate=7:1) to give 0.4 g of the desired product as pale yellow liquid. After completion of the reaction separated oily product was extracted with ethyl acetate The extract was washed with water dried over anhydrous sodium sulfate and ethyl acetate was distilled off under reduced pressure The oily product obtained

Conditions: temp:10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A Grignard solution prepared from 2-bromopentane (227.3 g, 1.5 moles) and magnesium (39.6 g) in tetrahydrofuran (500 cm3) was estimated by a standard procedure and found to contain 1.05 moles of 2-pentyl magnesium bromide. The solution was diluted with diethyl ether (250 cm3) and cooled to 10° C. in an atmosphere of nitrogen. A solution of dibutyl phosphate (67.9 g, 0.35 moles) in diethyl ether (500 cm3) was added with stirring during 1 hr. whilst the temperature was maintained at 10°-15° C. The solution was then boiled under reflux for ten min. to complete the reaction. The solution was cooled to 10° C. and 25% aqueous sulphuric acid (500 cm3) was added with stirring during 1 hr. The organic layer was separated and successively extracted with water (two 300 cm3 amounts), 10% aqueous sodium bicarbonate (300 cm3), and water (two 300 cm3 amounts). It was then dried (magnesium sulphate) and filtered and distilled yielding di-2-pentylphosphine oxide (35.0 g ), b.p. 110° C. at a pressure of 0.8 mm of mercury. All of this compound was stirred in nitrogen atmosphere with phosphorus trichloride (10 cm3) at 22° C. After 1 hr. it was found by gas chromatography that about 20% remained unreacted; a second addition of phosphorus trichloride (10 cm3) was made and stirring was continued for a further 2 hr. when reaction had reached about 95% completion. The solution was distilled yielding volatile phosphorus compounds and finally chloro di-2-pentylphosphine (27.5 g), b.p. 72°-74° C. under a pressure of 1.5 mm of mercury. whilst the temperature was maintained at 10°-15° C under reflux for ten min. the reaction The solution was cooled to 10° C. with stirring during 1 hr The organic layer was separated successively extracted with water (two 300 cm3 amounts), 10% aqueous sodium bicarbonate (300 cm3), and water (two 300 cm3 amounts) It was then dried (magnesium sulphate) filtered distilled

Conditions: temp:10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A Grignard solution prepared from 2-bromopentane (227.3 g, 1.5 moles) and magnesium (39.6 g) in tetrahydrofuran (500 cm3) was estimated by a standard procedure and found to contain 1.05 moles of 2-pentyl magnesium bromide. The solution was diluted with diethyl ether (250 cm3) and cooled to 10° C. in an atmosphere of nitrogen. A solution of dibutyl phosphate (67.9 g, 0.35 moles) in diethyl ether (500 cm3) was added with stirring during 1 hr. whilst the temperature was maintained at 10°-15° C. The solution was then boiled under reflux for ten min. to complete the reaction. The solution was cooled to 10° C. and 25% aqueous sulphuric acid (500 cm3) was added with stirring during 1 hr. The organic layer was separated and successively extracted with water (two 300 cm3 amounts), 10% aqueous sodium bicarbonate (300 cm3), and water (two 300 cm3 amounts). It was then dried (magnesium sulphate) and filtered and distilled yielding di-2-pentylphosphine oxide (35.0 g ), b.p. 110° C. at a pressure of 0.8 mm of mercury. All of this compound was stirred in nitrogen atmosphere with phosphorus trichloride (10 cm3) at 22° C. After 1 hr. it was found by gas chromatography that about 20% remained unreacted; a second addition of phosphorus trichloride (10 cm3) was made and stirring was continued for a further 2 hr. when reaction had reached about 95% completion. The solution was distilled yielding volatile phosphorus compounds and finally chloro di-2-pentylphosphine (27.5 g), b.p. 72°-74° C. under a pressure of 1.5 mm of mercury. whilst the temperature was maintained at 10°-15° C under reflux for ten min. the reaction The solution was cooled to 10° C. with stirring during 1 hr The organic layer was separated successively extracted with water (two 300 cm3 amounts), 10% aqueous sodium bicarbonate (300 cm3), and water (two 300 cm3 amounts) It was then dried (magnesium sulphate) filtered distilled

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

Procedure: In the same manner, ethyl N-{2-(4-hydroxyphenoxy]ethyl}carbamate (1.25 g, 5.5 mmol) and sodium hydride, prewashed with pentane, (0.132 g, 5.5 mmol) are reacted together, followed by addition of 1-methylbutyl bromide. The mixture is heated at 50° for 20 hours, then worked up and purified by prep. TLC to give ethyl N-{2-[4-(1-methylbutoxy)phenoxy]ethyl}carbamate (compound 14, Table A). are reacted together The mixture is heated at 50° for 20 hours purified by prep

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

Procedure: In the same manner, ethyl N-{2-(4-hydroxyphenoxy]ethyl}carbamate (1.25 g, 5.5 mmol) and sodium hydride, prewashed with pentane, (0.132 g, 5.5 mmol) are reacted together, followed by addition of 1-methylbutyl bromide. The mixture is heated at 50° for 20 hours, then worked up and purified by prep. TLC to give ethyl N-{2-[4-(1-methylbutoxy)phenoxy]ethyl}carbamate (compound 14, Table A). are reacted together The mixture is heated at 50° for 20 hours purified by prep

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

Procedure: Sodium metal (5.24 g, 0.23 g atm) was reacted with 25 mL of absolute ethanol. To this solution was added dropwise, with stirring, diethyl malonate (36.0 mL, 0.24 mol). The solution was heated to reflux and 2-bromopentane (29.0 mL, 0.23 mol) was added dropwise. After refluxing overnight, the reaction was cooled and the ethanol removed on a rotovap. The product was washed with water, dried with MgSO4 and fractionally distilled to give 35.7 g of the desired product. To this solution was added dropwise The solution was heated to reflux After refluxing overnight the reaction was cooled the ethanol removed on a rotovap The product was washed with water dried with MgSO4 fractionally distilled

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

Procedure: Using the general method of Compound 42 Part B, 2-bromopentane (2.7 mL, 21.7 mmole) was reacted with 1-benzyloxy-3-phenylurea (4.9 g, 20.1 mmole) to provide 4.26 g of 1-benzyloxy-1-(1-methylbutyl)-3-phenylurea as a yellow oil.