diethoxy(methyl)phosphane

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:

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

Procedure: A solution of 1,4,5-triphenyl-2-(7-bromoheptyloxy)-imidazole (1.75 g) and diethyl methylphosphonite (2.45 g) in toluene (10 ml) was heated at reflux temperature for 48 hours. Methanol and water were added and the mixture evaporated to an oil. This was chromatographed on silica gel (ethyl acetate/ethanol). The resulting oil slowly crystallised and was triturated with ether/petroleum ether, filtered then recrystallised from ethanol/ether to give ethyl 7-(1,4,5-triphenyl-imidazol-2-yloxy)heptane-methylphosphinate (1.06 g, 57%) as a white solid, m.p. 101°-2° C. Found: C, 72.05; H, 7.26; N, 5.52%; C31H37N2O3P; Requires: C, 72.07; H, 7.22; N, 5.42%. at reflux temperature for 48 hours the mixture evaporated to an oil This was chromatographed on silica gel (ethyl acetate/ethanol) The resulting oil slowly crystallised was triturated with ether/petroleum ether filtered then recrystallised from ethanol/ether

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

Procedure: A solution of 1,4,5-triphenyl-2-(7-bromoheptyloxy)-imidazole (1.75 g) and diethyl methylphosphonite (2.45 g) in toluene (10 ml) was heated at reflux temperature for 48 hours. Methanol and water were added and the mixture evaporated to an oil. This was chromatographed on silica gel (ethyl acetate/ethanol). The resulting oil slowly crystallised and was triturated with ether/petroleum ether, filtered then recrystallised from ethanol/ether to give ethyl 7-(1,4,5-triphenyl-imidazol-2-yloxy)heptane-methylphosphinate (1.06 g, 57%) as a white solid, m.p. 101°-2° C. Found: C, 72.05; H, 7.26; N, 5.52%; C31H37N2O3P; Requires: C, 72.07; H, 7.22; N, 5.42%. at reflux temperature for 48 hours the mixture evaporated to an oil This was chromatographed on silica gel (ethyl acetate/ethanol) The resulting oil slowly crystallised was triturated with ether/petroleum ether filtered then recrystallised from ethanol/ether

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5.30 g (16.1 mmol) of (4S)-3-benzyloxycarbonyl-4-(2-bromomethyl)-1,3-oxazolidin-5-one (from Example 5) are mixed with 4.40 g (32.3 mmol) of diethyl methanephosphonite and the mixture is heated under argon for 6 hours at 120° C. The excess diethyl methanephosphonite is distilled off in high vacuum and the residue is purified by chromatography on silica gel (mobile phase: dichloromethane/acetonitrile). 4.64 g (81.1% of theory) of (4S)-3-benzyloxycarbonyl-4-{2-[ethoxy(methyl)phosphinyl]ethyl}-1,3-oxazolidin-5-one are obtained as a colorless oil. Analytical data: The excess diethyl methanephosphonite is distilled off in high vacuum the residue is purified by chromatography on silica gel (mobile phase: dichloromethane/acetonitrile)

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Diethyl methylphosphonite (0.15 ml, 0.992 mmol), tert-butyl (2E)-3-(3-bromophenyl)acrylate (0.25 g, 0.883 mmol), triethylamine (0.37 ml, 2.65 mmol), and tetrakis(triphenylphosphine)palladium(0) (0.1559 g, 0.135 mmol) were combined and allowed to heat at 100° C. for approximately eight hours. The reaction was cooled and filtered over celite, washing with ethyl acetate. The filtrate was concentrated under reduced pressure. The residue was purified by column chromatography on silica gel, eluting with EtOAc/hexane. MS: calc'd 311 (MH+), exp 311 (MH+). The reaction was cooled filtered over celite washing with ethyl acetate The filtrate was concentrated under reduced pressure The residue was purified by column chromatography on silica gel eluting with EtOAc/hexane

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

Procedure: 1-(4-bromophenyl)-3-chloropropan-1-one (4.5 g, 18.18 mmol) and diethyl methylphosphonite (6 g, 44.1 mmol) were stirred in refluxing toluene (9 mL) for 5 hours. Room temperature was attained and the solvent removed in vacuo. Purification of the residue by MPLC (0-10% MeOH-EtOAc) gave ethyl [3-(4-bromophenyl)-3-oxopropyl]methylphosphinate as a pale yellow oil that crystallised on standing. Room temperature the solvent removed in vacuo Purification of the residue by MPLC (0-10% MeOH-EtOAc)

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

Procedure: 1-(4-bromophenyl)-3-chloropropan-1-one (4.5 g, 18.18 mmol) and diethyl methylphosphonite (6 g, 44.1 mmol) were stirred in refluxing toluene (9 mL) for 5 hours. Room temperature was attained and the solvent removed in vacuo. Purification of the residue by MPLC (0-10% MeOH-EtOAc) gave ethyl [3-(4-bromophenyl)-3-oxopropyl]methylphosphinate as a pale yellow oil that crystallised on standing. Room temperature the solvent removed in vacuo Purification of the residue by MPLC (0-10% MeOH-EtOAc)