undecanoyl chloride

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:0.00; pressure:0.00; stir:

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

Procedure: According to the same procedure as described in Preparation 1, hydroquinone and n-undecanoyl chloride (prepared by chlorination of n-undecanoic acid with thionyl chloride) were reacted and the reaction mixture was extracted with ethyl acetate. The ethyl acetate extract was concentrated and the residue was dissolved in n-hexane and crystallized with cooling to give crude hydroquinone monoundecanoate. The crude product was recrystallized from n-hexane. m.p. 72°-74° C. were reacted the reaction mixture was extracted with ethyl acetate The ethyl acetate extract was concentrated the residue was dissolved in n-hexane crystallized with cooling

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

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

Procedure: 161 mg of (±)-6-fluoro-8-amino-2,3-dihydrospiro[4H-1-benzopyran-4,5'-thiazolidine]-2',4'-dione were dissolved in 3.5 ml of pyridine and esterified with 135 mg of undecanoyl chloride. After stirring at room temperature for 6 hours, the majority of the pyridine was removed in vacuo, the residue was extracted with three portions of ethyl acetate and two portions of 1N hydrochloric acid, the organic phases were washed neutral with water and with saturated sodium chloride solution, dried with sodium sulfate and concentrated. The residue was chromatographed on silica gel with chloroform/methanol (19:1). With Rf =0.27 there were eluted 182 mg of material in the form of a resin which yielded, from methanol, (±)-6-fluoro-8-undecylamido-2,3-dihydrospiro[4H-1-benzopyran-4,5'-thiazolidine]-2',4'-dione in the form of colorless crystals of melting point 69°-71° C. the majority of the pyridine was removed in vacuo the residue was extracted with three portions of ethyl acetate and two portions of 1N hydrochloric acid the organic phases were washed neutral with water and with saturated sodium chloride solution dried with sodium sulfate concentrated The residue was chromatographed on silica gel with chloroform/methanol (19:1) With Rf =0.27 there were eluted 182 mg of material in the form of a resin which

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

Procedure: 161 mg of (±)-6-fluoro-8-amino-2,3-dihydrospiro[4H-1-benzopyran-4,5'-thiazolidine]-2',4'-dione were dissolved in 3.5 ml of pyridine and esterified with 135 mg of undecanoyl chloride. After stirring at room temperature for 6 hours, the majority of the pyridine was removed in vacuo, the residue was extracted with three portions of ethyl acetate and two portions of 1N hydrochloric acid, the organic phases were washed neutral with water and with saturated sodium chloride solution, dried with sodium sulfate and concentrated. The residue was chromatographed on silica gel with chloroform/methanol (19:1). With Rf =0.27 there were eluted 182 mg of material in the form of a resin which yielded, from methanol, (±)-6-fluoro-8-undecylamido-2,3-dihydrospiro[4H-1-benzopyran-4,5'-thiazolidine]-2',4'-dione in the form of colorless crystals of melting point 69°-71° C. the majority of the pyridine was removed in vacuo the residue was extracted with three portions of ethyl acetate and two portions of 1N hydrochloric acid the organic phases were washed neutral with water and with saturated sodium chloride solution dried with sodium sulfate concentrated The residue was chromatographed on silica gel with chloroform/methanol (19:1) With Rf =0.27 there were eluted 182 mg of material in the form of a resin which

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

Procedure: To a solution of p-hydroxybenzoic acid (3 g) and triethylamine (2.4 g) in dichloromethane (30 ml) were added undecanoyl chloride (4.5 g) and dimethylaminopyridine (0.2 g). The mixture was stirred at room temperature for about 20 hours. After dilute aqueous hydrochloric acid solution was added, an organic layer was separated by a funnel. After the solution was distilled to remove the solvent, the residue was washed with n-hexane and dried to obtain the titled compound (about 5 g). an organic layer was separated by a funnel After the solution was distilled to remove the solvent the residue was washed with n-hexane dried

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

Procedure: To a solution of p-hydroxybenzoic acid (3 g) and triethylamine (2.4 g) in dichloromethane (30 ml) were added undecanoyl chloride (4.5 g) and dimethylaminopyridine (0.2 g). The mixture was stirred at room temperature for about 20 hours. After dilute aqueous hydrochloric acid solution was added, an organic layer was separated by a funnel. After the solution was distilled to remove the solvent, the residue was washed with n-hexane and dried to obtain the titled compound (about 5 g). an organic layer was separated by a funnel After the solution was distilled to remove the solvent the residue was washed with n-hexane dried

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

Procedure: To a solution of 22.0 g (108 mM) of undecanoyl chloride in 185 ml of pyridine, 22.2 g (110 mM) of 4-methoxyphenacylamine hydrochloride was gradually added in 30 minutes under cooling and stirring below -5° C., followed by stirring for 30 minutes below -5° C. and heat-refluxing of 1 hour under stirring. After the reaction, the reaction mixture was cooled to room temperature and poured into 1 liter of cool water to precipitate a crystal. The crystal was recovered by filtration, washed with water and recrystallized from ethanol to obtain 13.9 g of decanoyl-4-methoxyphenacylamine (Yield: 38.8%). under cooling by stirring for 30 minutes below -5° C. heat-refluxing of 1 hour under stirring After the reaction to precipitate a crystal The crystal was recovered by filtration washed with water recrystallized from ethanol