diethyl hydrogen phosphite

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol, 1.0 eq.) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol, 1.0 eq.) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol, 3.0 eq.) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol, 1.0 eq.) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol, 1.0 eq.) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol, 1.0 eq.) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol, 3.0 eq.) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol, 1.0 eq.) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol, 1.0 eq.) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol, 1.0 eq.) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol, 3.0 eq.) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol, 1.0 eq.) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum

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

Procedure: To a 5-liter vessel equipped with a mechanical stirrer was added 863 ml (6.7 mol) of diethyl hydrogen phosphite (DEHP). The stirred DEHP was heated to 140° and then 12.3 ml (0.067 mol) of di-tertiary-butyl peroxide was added. Finally, α-pinene, 211 ml (1.3 mol), was added dropwise over a period of 10-30 minutes while the reaction temperture was maintained at 140°-150°. This mixture was heated for 5 hours at 140°, cooled at room temperature, and then distilled in vacuo to yield 54.2 g (0.2 mol; 15.4%) of diethyl para-menth-6-en-2-ylphosphonate, bp=180°-185° (1.2 mm), and 376.5 g (0.91 mol, 70.0%) of tetraethyl-para-menthane-2,6-diyldiphosphonate), bp=198° (0.4 mm). The NMR spectrum showed an A2B3 pattern corresponding to the ethyl groups at 4.12δ and 1.35δ along with the remainder of the proton signals between 2.5δ and 0.8δ. To a 5-liter vessel equipped with a mechanical stirrer was maintained at 140°-150° This mixture was heated for 5 hours at 140° distilled in vacuo

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol, 1.0 eq.) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol, 1.0 eq.) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol, 3.0 eq.) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol, 1.0 eq.) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum

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

Procedure: Diethyl hydrogen phosphite (1.0 mole) and diethyl amine (1.0 mole) were combined in a round bottom flask. Diethyl acetylphosphonate (1.0 mole) was added dropwise, with stirring. The reaction mixture was maintained at a temperature of about 75° C. for an additional 2 hours after all of the diethyl acetyl phosphonate was added. The resulting mixture was distilled under reduced pressure to yield tetraethyl 1-hydroxyethylidene bisphosphonic acid as a pale yellowish liquid which crystallized at -15° C. into small needle-shaped crystals. was added The resulting mixture was distilled under reduced pressure

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

Procedure: 27 parts of sodium 1-(2'-bromo-4'-nitrophenylazo)-2-hydroxy-6-naphthylsulphonate are stirred with 130 ml of water, and 20 parts of copper sulphate 5-hydrate in 70 parts of water are added. The pH value is adjusted to 7-8 and the mixture is stirred for one hour. Thereafter, 35 parts of phosphorous acid diethyl ester are added dropwise at pH 8. The mixture is subsequently stirred at room temperature for 4 hours and acidified with hydrochloric acid. The precipitate is filtered off, washed and dried and gives 23 parts of diethyl 5-nitro-2-[2'-hydroxy-6'-sulphonaphthylazo]-phenylphosphonate almost free from starting compounds and by-products. are added The mixture is subsequently stirred at room temperature for 4 hours The precipitate is filtered off washed dried

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

Procedure: 100 parts by weight of diethyl hydrogen phosphite and 50 parts by weight of phosphoric acid are mixed and reacted. The reaction is exothermic and the temperature of the reactants are keep below their boiling point for 30 minutes to 1 hour thereby producing a diethyl hydrogen-phosphoric acid compound. reacted for 30 minutes to 1 hour

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 2-oxoacetate (50%) (74 g, 724.8 mmol, 1.0 eq.) was added dropwise with stirring at 0° C. to a solution of diethyl hydrogen phosphite (50 g, 362.1 mmol, 1.0 eq.) in toluene (100 mL), under nitrogen. Et3N (110 g, 1.1 mol, 3.0 eq.) was added dropwise with stirring at 0° C. The resulting solution was stirred for 1 hour at room temperature. To the mixture was added acetic anhydride (37 g, 362.4 mmol, 1.0 eq.) dropwise with stirring at 0° C. The resulting solution was stirred overnight at room temperature. The pH value of the solution was adjusted to 6 with 2N HCl. The resulting solution was extracted with DCM (3×150 mL) and the organic layers were combined, dried over Na2SO4, and concentrated under vacuum. The residue was loaded onto a silica gel column with EtOAc:hexanes (1:2˜1:5) to yield the title compound (52 g) as a light yellow liquid. The resulting solution was stirred for 1 hour at room temperature with stirring at 0° C The resulting solution was stirred overnight at room temperature The resulting solution was extracted with DCM (3×150 mL) dried over Na2SO4 concentrated under vacuum