(4S)-4-(methoxymethyl)-1,3-dioxolan-2-one

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Benzylurethane (15.0 g, 83.9 mmol) was dissolved in dimethyl sulfoxide (40 mL), and thereto were added cesium fluoride (1.16 g, 7.63 mmol) and (S)-4-methoxymethyl-1,3- dioxolan-2-one (10.0 g, 76.3 mmol, optical purity 98.4%ee), in order. The mixture was stirred for 28 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by silica gel chromatography to give the subject (R)-3-benzyl-5-methoxymethyloxazolidin-2-one (14.1 g, yield 83.5%, optical purity 98.2%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by silica gel chromatography

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Benzylurethane (15.0 g, 83.9 mmol) was dissolved in dimethyl sulfoxide (40 mL), and thereto were added cesium fluoride (1.16 g, 7.63 mmol) and (S)-4-methoxymethyl-1,3- dioxolan-2-one (10.0 g, 76.3 mmol, optical purity 98.4%ee), in order. The mixture was stirred for 28 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by silica gel chromatography to give the subject (R)-3-benzyl-5-methoxymethyloxazolidin-2-one (14.1 g, yield 83.5%, optical purity 98.2%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by silica gel chromatography

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Urethane (37.4 g, 0.420 mmol) was dissolved in N,N-dimethylformamide (200 mL), and thereto were added cesium fluoride (5.80 g, 38.2 mmol) and (S)-4-methoxymethyl-1,3-dioxolan-2-one (50 g, 0.382 mol, optical purity 97.7%ee), in order. The mixture was stirred for 72 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by distillation to give the subject (R)-5-methoxymethyloxazolidin-2-one (35.1 g, yield 69.6 %, optical purity 97.3%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by distillation

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Urea (246 g, 4.09 mmol) was dissolved in dimethyl sulfoxide (2.27 L), and thereto were added cerium fluoride (69.0 g, 0.454 mol) and (S)-4-methoxymethyl-1,3-dioxolan-2-one (600 g, 4.54 mol, optical purity 98.9%ee), in order. The mixture was stirred for 36 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by distillation to give the subject (R)-5-methoxymethyloxazolidin-2-one (445 g, yield 74.7%, optical purity 98.6%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by distillation

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

Procedure: A solution of 4.2 g (9.9 mmol) of 2-(2-phenylmethoxy-3,3,3-trifluoropropyl)-6-ethoxycarbonylamino-3,4-dihydro-2H-1-benzopyran in 40 ml of dimethylformamide is stirred for 24 hours, at 130° C., in the presence of 140 mg (1.0 mmol) of potassium carbonate and of 3.4 g (26 mmol) of 4(S)-methoxymethyl-1,3-dioxolan-2-one added in 3 hours. The mixture is cooled, diluted with water and the product is extracted with diethyl ether. The organic phase is then dried over sodium sulfate, concentrated under reduced pressure and chromatographed on a silica column using a 30/70 mixture of ethyl acetate and cyclohexane. The product obtained is used as such in the following step. added in 3 hours The mixture is cooled the product is extracted with diethyl ether The organic phase is then dried over sodium sulfate concentrated under reduced pressure chromatographed on a silica column a 30/70 mixture of ethyl acetate and cyclohexane The product obtained

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

Procedure: A suspension of 500 mg (1.84 mmol) of trans-[4-(4-cyano-cyclohexyl)-phenyl]-ethoxycarbamic acid, 365 mg (2.8 mmol) of (S)-4-methoxymethyl-1,3-dioxolan-2-one and 185 mg of potassium carbonate was stirred at 160° for 16 hours. The reaction mixture was chromatographed over silica gel with ethyl acetate/hexane 1:1 and the yellow crystals obtained were recrystallized from ethyl acetate. 165 mg (29%) were obtained as white crystals with m.p. 174°. The reaction mixture was chromatographed over silica gel with ethyl acetate/hexane 1:1 the yellow crystals obtained were recrystallized from ethyl acetate 165 mg (29%) were obtained as white crystals with m.p. 174°

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

Procedure: 3.1 g (11 mmol) of 5-ethoxycarbonylamino-2-phenylbenzofuran are treated with 4(S)-methoxymethyl-1,3-dioxolan-2-one under the conditions described in step 4 of Example 1. 2.5 g of product are obtained. Melting point: 178.5-179.3° C.

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Benzylurethane (15.0 g, 83.9 mmol) was dissolved in dimethyl sulfoxide (40 mL), and thereto were added cesium fluoride (1.16 g, 7.63 mmol) and (S)-4-methoxymethyl-1,3- dioxolan-2-one (10.0 g, 76.3 mmol, optical purity 98.4%ee), in order. The mixture was stirred for 28 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by silica gel chromatography to give the subject (R)-3-benzyl-5-methoxymethyloxazolidin-2-one (14.1 g, yield 83.5%, optical purity 98.2%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by silica gel chromatography

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Urethane (37.4 g, 0.420 mmol) was dissolved in N,N-dimethylformamide (200 mL), and thereto were added cesium fluoride (5.80 g, 38.2 mmol) and (S)-4-methoxymethyl-1,3-dioxolan-2-one (50 g, 0.382 mol, optical purity 97.7%ee), in order. The mixture was stirred for 72 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by distillation to give the subject (R)-5-methoxymethyloxazolidin-2-one (35.1 g, yield 69.6 %, optical purity 97.3%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by distillation

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Urea (246 g, 4.09 mmol) was dissolved in dimethyl sulfoxide (2.27 L), and thereto were added cerium fluoride (69.0 g, 0.454 mol) and (S)-4-methoxymethyl-1,3-dioxolan-2-one (600 g, 4.54 mol, optical purity 98.9%ee), in order. The mixture was stirred for 36 hours at 140° C. under an atmosphere of argon. After filtering off the insoluble materials, the filtrate was condensed in vacuo, and the residue was purified by distillation to give the subject (R)-5-methoxymethyloxazolidin-2-one (445 g, yield 74.7%, optical purity 98.6%ee). After filtering off the insoluble materials condensed in vacuo the residue was purified by distillation

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

Procedure: A solution of 4.2 g (9.9 mmol) of 2-(2-phenylmethoxy-3,3,3-trifluoropropyl)-6-ethoxycarbonylamino-3,4-dihydro-2H-1-benzopyran in 40 ml of dimethylformamide is stirred for 24 hours, at 130° C., in the presence of 140 mg (1.0 mmol) of potassium carbonate and of 3.4 g (26 mmol) of 4(S)-methoxymethyl-1,3-dioxolan-2-one added in 3 hours. The mixture is cooled, diluted with water and the product is extracted with diethyl ether. The organic phase is then dried over sodium sulfate, concentrated under reduced pressure and chromatographed on a silica column using a 30/70 mixture of ethyl acetate and cyclohexane. The product obtained is used as such in the following step. added in 3 hours The mixture is cooled the product is extracted with diethyl ether The organic phase is then dried over sodium sulfate concentrated under reduced pressure chromatographed on a silica column a 30/70 mixture of ethyl acetate and cyclohexane The product obtained