2-methyl-2-nitropropane-1,3-diol

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 1,3-dicyclohexylcarbodiimide (4.23 g, 20.5 mmol), (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 4.34 g, 18.9 mmol), and 2-nitro-2-methyl-1,3-propanediol (2.56 g, 19.0 mmol) in CH2Cl2 (50 mL) and THF (50 mL) was stirred at ambient temperature overnight. The solvent was evaporated and EtOAc (100 mL) was added to the resulting crude material, cooled in a dry-ice bath and the byproduct, dicyclohexyl urea was removed by filtration. The product was separated by silica gel column chromatography eluting with ethyl acetate/hexane (1:3, Rf=0.1) to give the title compound (a mixture of diasteromers) as an oil (2.77 g, 42% yield). 1H NMR (300 MHz, CDCl3) δ 7.69-7.60 (m, 3H), 7.34-7.3 (m, 1H), 7.14-7.08 (m, 2H), 4.44 (d, J=4.2 Hz, 2H), 3.86 (s, 3H), 3.85 (q, J=7.2 Hz, 1H), 1.55 (d, J=7.2 Hz, 3H), 1.36 & 1.40 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 174.14, 174.02 157.57, 134.53, 134.51, 133.64, 129.13, 128.7, 127.17, 125.87, 125.84, 119.0, 105.47, 89.53, 89.42, 64.67, 64.52, 64.19, 55.12, 45.04, 18.25, 18.03, 17.82, 17.79. Mass spectrum (API-TIS) m/z 348 (MH)−. The solvent was evaporated EtOAc (100 mL) was added to the resulting crude material cooled in a dry-ice bath the byproduct, dicyclohexyl urea was removed by filtration The product was separated by silica gel column chromatography eluting with ethyl acetate/hexane (1:3, Rf=0.1)

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

Procedure: A solution of 2-methyl-2-nitro-1,3-propanediol and ethylene carbonate is heated overnight. The reaction mixture is diluted with ethyl acetate and the solution is washed with water. The organic phase is dried and concentrated to obtain 5-methyl-5-nitro-1,3-dioxan-2-one. This is dissolved in methanol and hydrogenated under pressure to give the 5amino compound which is acylated with dodecanoyl chloride to give the product. the solution is washed with water The organic phase is dried concentrated

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

Procedure: To a solution of 2-nitro-2-methyl-1,3-propanediol (20.4 g, 151 mmol) in 40% aqueous methylamine (11.7 g, 151 mmol), was added an aqueous solution of formaldehyde (37%, 12.2 g, 151 mmol). The reaction was stirred at room temperature for one week, then extracted with ether three times. The organic fractions were dried over sodium sulfate and concentrated under reduced pressure to give a crude oil which was purified by column chromatography, eluting from silica gel with a gradient of 50-100% ethyl acetate in hexanes to give 15.4 g of desired product (63% yield). 1H NMR (400 MHz, CDCl3) δ 1.45 (s, 3H), 2.32 (s, 3H), 2.63-2.66 (d, J=13.2 Hz, 1H), 3.51-3.54 (d, J=12.6 Hz, 1H), 3.67-3.71 (d of trip, J=1.9, 13.2 Hz, 1H), 3.86-3.89 (d, J=8.5 Hz, 1H), 4.29-4.32 (dd, J=1.2, 8.6 Hz, 1H), 4.61-4.66 (dd, J=2.4, 12.6 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ 22.0, 39.9, 59.8, 71.2, 83.1, 86.1. LRMS (ESI/APCI): 161[M+H]+. extracted with ether three times The organic fractions were dried over sodium sulfate concentrated under reduced pressure to give a crude oil which was purified by column chromatography eluting from silica gel with a gradient of 50-100% ethyl acetate in hexanes

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

Procedure: To a solution of 2-nitro-2-methyl-1,3-propanediol (20.4 g, 151 mmol) in 40% aqueous methylamine (11.7 g, 151 mmol), was added an aqueous solution of formaldehyde (37%, 12.2 g, 151 mmol). The reaction was stirred at room temperature for one week, then extracted with ether three times. The organic fractions were dried over sodium sulfate and concentrated under reduced pressure to give a crude oil which was purified by column chromatography, eluting from silica gel with a gradient of 50-100% ethyl acetate in hexanes to give 15.4 g of desired product (63% yield). 1H NMR (400 MHz, CDCl3) δ 1.45 (s, 3H), 2.32 (s, 3H), 2.63-2.66 (d, J=13.2 Hz, 1H), 3.51-3.54 (d, J=12.6 Hz, 1H), 3.67-3.71 (d of trip, J=1.9, 13.2 Hz, 1H), 3.86-3.89 (d, J=8.5 Hz, 1H), 4.29-4.32 (dd, J=1.2, 8.6 Hz, 1H), 4.61-4.66 (dd, J=2.4, 12.6 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ 22.0, 39.9, 59.8, 71.2, 83.1, 86.1. LRMS (ESI/APCI): 161[M+H]+. extracted with ether three times The organic fractions were dried over sodium sulfate concentrated under reduced pressure to give a crude oil which was purified by column chromatography eluting from silica gel with a gradient of 50-100% ethyl acetate in hexanes

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

Procedure: To a solution of triflic anhydride (16.5 ml, 0.1 mol) in chloroform (50 ml) is added a solution of 2-methyl-2-nitro-1,3-propanediol (6.75 g, 0.05 mol) and pyridine (8.85 ml, 0.11 mol) in chloroform (50 ml) with external cooling to ensure a temperature of between 0° and 5° C. during the addition. After the addition the cooling bath is removed and the reaction stirred for 18 hours at ambient temperature. The reaction mixture is transferred to a separating funnel and washed with water. The organic layer is dried (Na2SO4), filtered and evaporated to dryness. The crude product is purified by chromatography using a 4:1 mixture of Hexane:Ethyl acetate as eluant; the product is obtained as a solid with melting point 50-52° C. with external cooling a temperature of between 0° and 5° C. during the addition After the addition the cooling bath is removed The reaction mixture is transferred to a separating funnel washed with water The organic layer is dried (Na2SO4) filtered evaporated to dryness The crude product is purified by chromatography a 4:1 mixture of Hexane the product is obtained as a solid with melting point 50-52° C.

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

Procedure: To a solution of 2-methyl-2-nitro-1,3-propanediol (80 g, 0.592 mol) and triethylamine (131.8 g, 1.303 mol) in diethyl ether (250 ml) is added a solution of tosyl chloride (225.7 g, 1.184 mol) in diethyl ether (800 ml) between −15° and −20° C. The resulting suspension is stirred at 0° C. for 1 hour, then 18 hours at ambient temperature. The reaction mixture is filtered, the solid residue is taken up twice in ethyl acetate and stirred, the suspension being filtered again. The combined ethyl acetate layers are evaporated to dryness giving a first crop of crude product (175.8 g). The ether filtrate is washed with water (2×) and brine, dried (Na2SO4), filtered, and partly concentrated. The suspension is filtered giving another 15.0 g of product. The crude solid product (190.8 g, 73%) is used in the next step without further purification. 18 hours at ambient temperature The reaction mixture is filtered stirred the suspension being filtered again The combined ethyl acetate layers are evaporated to dryness giving a first crop of crude product (175.8 g) The ether filtrate is washed with water (2×) and brine dried (Na2SO4) filtered partly concentrated The suspension is filtered

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

Procedure: A solution of 1,3-dicyclohexylcarbodiimide (4.23 g, 20.5 mmol), (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 4.34 g, 18.9 mmol), and 2-nitro-2-methyl-1,3-propanediol (2.56 g, 19.0 mmol) in CH2Cl2 (50 mL) and THF (50 mL) was stirred at ambient temperature overnight. The solvent was evaporated and EtOAc (100 mL) was added to the resulting crude material, cooled in a dry-ice bath and the byproduct, dicyclohexyl urea was removed by filtration. The product was separated by silica gel column chromatography eluting with ethyl acetate/hexane (1:3, Rf=0.1) to give the title compound (a mixture of diasteromers) as an oil (2.77 g, 42% yield). 1H NMR (300 MHz, CDCl3) δ 7.69-7.60 (m, 3H), 7.34-7.3 (m, 1H), 7.14-7.08 (m, 2H), 4.44 (d, J=4.2 Hz, 2H), 3.86 (s, 3H), 3.85 (q, J=7.2 Hz, 1H), 1.55 (d, J=7.2 Hz, 3H), 1.36 & 1.40 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 174.14, 174.02 157.57, 134.53, 134.51, 133.64, 129.13, 128.7, 127.17, 125.87, 125.84, 119.0, 105.47, 89.53, 89.42, 64.67, 64.52, 64.19, 55.12, 45.04, 18.25, 18.03, 17.82, 17.79. Mass spectrum (API-TIS) m/z 348 (MH)−. The solvent was evaporated EtOAc (100 mL) was added to the resulting crude material cooled in a dry-ice bath the byproduct, dicyclohexyl urea was removed by filtration The product was separated by silica gel column chromatography eluting with ethyl acetate/hexane (1:3, Rf=0.1)

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

Procedure: A solution of 2-methyl-2-nitro-1,3-propanediol and ethylene carbonate is heated overnight. The reaction mixture is diluted with ethyl acetate and the solution is washed with water. The organic phase is dried and concentrated to obtain 5-methyl-5-nitro-1,3-dioxan-2-one. This is dissolved in methanol and hydrogenated under pressure to give the 5amino compound which is acylated with dodecanoyl chloride to give the product. the solution is washed with water The organic phase is dried concentrated

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

Procedure: A solution of 2-methyl-2-nitro-1,3-propanediol and ethylene carbonate is heated overnight. The reaction mixture is diluted with ethyl acetate and the solution is washed with water. The organic phase is dried and concentrated to obtain 5-methyl-5-nitro-1,3-dioxan-2-one. This is dissolved in methanol and hydrogenated under pressure to give the 5amino compound which is acylated with dodecanoyl chloride to give the product. the solution is washed with water The organic phase is dried concentrated

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 1,3-dicyclohexylcarbodiimide (4.23 g, 20.5 mmol), (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 4.34 g, 18.9 mmol), and 2-nitro-2-methyl-1,3-propanediol (2.56 g, 19.0 mmol) in CH2Cl2 (50 mL) and THF (50 mL) was stirred at ambient temperature overnight. The solvent was evaporated and EtOAc (100 mL) was added to the resulting crude material, cooled in a dry-ice bath and the byproduct, dicyclohexyl urea was removed by filtration. The product was separated by silica gel column chromatography eluting with ethyl acetate/hexane (1:3, Rf=0.1) to give the title compound (a mixture of diasteromers) as an oil (2.77 g, 42% yield). 1H NMR (300 MHz, CDCl3) δ 7.69-7.60 (m, 3H), 7.34-7.3 (m, 1H), 7.14-7.08 (m, 2H), 4.44 (d, J=4.2 Hz, 2H), 3.86 (s, 3H), 3.85 (q, J=7.2 Hz, 1H), 3.7 (m, 1H), 1.55 (d, J=7.2 Hz, 3H), 1.36 & 1.40 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 174.14, 174.02, 157.57, 134.53, 134.51, 133.64, 129.13, 128.7, 127.17, 125.87, 125.84, 119.0, 105.47, 89.53, 89.42, 64.67, 64.52, 64.19, 55.12, 45.04, 18.25, 18.03, 17.82, 17.79. Mass spectrum (API-TIS) m/z 348 (MH)+. The solvent was evaporated EtOAc (100 mL) was added to the resulting crude material cooled in a dry-ice bath the byproduct, dicyclohexyl urea was removed by filtration The product was separated by silica gel column chromatography eluting with ethyl acetate/hexane (1:3, Rf=0.1)