methyl 2-isocyanoacetate

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: To a suspension of potassium tert-butoxide (89 mg, 0.75 mmol) in THF (3 mL) is added methyl isocyanoacetate (65 μL, 0.68 mmol) followed by (S)-2-phenyl-4-(1-isothiocyanato-2-(4-nitrophenyl)ethyl)thiazole, 29, (250 mg, 0.68 mmol). The reaction mixture is stirred at room temperature for 2 hours then poured into sat. NaHCO3. The mixture is extracted with EtOAc (3×25 mL) and the combined organic layers are washed with brine and dried (Na2SO4) and concentrated in vacuo. The crude residue is purified over silica to afford 323 mg (˜100% yield) of the desired product as a slightly yellow solid. 1H NMR (300 MHz, CDCl3) δ 8.09-8.13 (m, 2H), 7.95-7.98 (m, 3H), 7.84 (d, J=1.2 Hz, 1H), 7.44-7.50 (m, 3H), 7.28-7.31 (m, 2H), 7.96 (d, J=0.6 Hz, 1H), 4.71-4.78 (m, 1H), 3.92 (s, 3H), 3.60 (dd, J=13.8 and 6.0 Hz, 1H), 3.45 (dd, J=13.8 and 6.0 Hz, 1H). The mixture is extracted with EtOAc (3×25 mL) the combined organic layers are washed with brine dried (Na2SO4) concentrated in vacuo The crude residue is purified over silica

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

Procedure: 4.0 g (15.3 mmol) of 6-(N-benzyloxycarbonylamino)-2-methylene-hexanal and 1.62 ml (16.8 mmol) of isocyanoacetic acid methyl ester are dissolved in 50 ml of toluene and added dropwise at 40° to a suspension of 0.12 g of 96.4% copper(I) oxide in 50 ml of toluene. The mixture is then stirred at room temperature for 2.5 hours, filtered, introduced into a column filled with 60 g of silica gel and extracted first with hexane/ethyl acetate (1:1) and then with ethyl acetate. 5-[6-(N-benzyloxycarbonylamino)hex-1-en-2-yl]-oxazoline-4-carboxylic acid methyl ester is obtained; oil. filtered introduced into a column filled with 60 g of silica gel extracted first with hexane/ethyl acetate (1:1)

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

Procedure: To a suspension of potassium tert-butoxide (89 mg, 0.75 mmol) in THF (3 mL) is added methyl isocyanoacetate (65 μL, 0.68 mmol) followed by (S)-2-phenyl-4-(1-isothiocyanato-2-(4-nitrophenyl)ethyl)thiazole, 43, (250 mg, 0.68 mmol). The reaction mixture is stirred at room temperature for 2 hours then poured into sat. NaHCO3. The mixture is extracted with EtOAc (3×25 mL) and the combined organic layers are washed with brine and dried (Na2SO4) and concentrated in vacuo. The crude residue is purified over silica to afford 323 mg (˜100% yield) of the desired product as a slightly yellow solid. 1H NMR (300 MHz, CDCl3) δ 8.09-8.13 (m, 2H), 7.95-7 98 (m, 3H), 7.84 (d, J=1.2 Hz, 1H), 7.44-7.50 (m, 3H), 7.28-7.31 (m, 2H), 7.96 (d, J=0.6 Hz, 1H), 4.71-4.78 (m, 1H), 3.92 (s, 3H), 3.60 (dd, J=13.8 and 6.0 Hz, 1H), 3.45 (dd, J=13.8 and 6.0 Hz, 1H). The mixture is extracted with EtOAc (3×25 mL) the combined organic layers are washed with brine dried (Na2SO4) concentrated in vacuo The crude residue is purified over silica

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

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

Conditions: temp:-50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of sodium methoxide (1.86 g) in DMF (30 ml) was added methyl isocyanoacetate (2.38 ml) dropwise at −50° C. and the mixture stirred for 30 min at −50° C. 2-Methylpropanoyl chloride (3.36 ml) was added gradually to the mixture at −50° C. and the mixture stirred for 2 h at −50° C. The mixture was diluted with DCM (50 ml) and saturated sodium bicarbonate solution (50 ml) was added and the organic layer collected using a hydrophobic frit. The aqueous layer was washed with DCM (2×50 ml) and separated by hydrophobic frit. The combined organic phases were concentrated in vacuo. This was purified by chromatography on silica gel, eluting with a gradient of 0-100% ethyl acetate in cyclohexane, followed by 0-20% methanol. The residue was distilled using a Kugelrohr to give the title compound (553 mg) as yellow solid. the mixture stirred for 2 h at −50° C was added the organic layer collected The aqueous layer was washed with DCM (2×50 ml) separated by hydrophobic frit The combined organic phases were concentrated in vacuo This was purified by chromatography on silica gel eluting with a gradient of 0-100% ethyl acetate in cyclohexane The residue was distilled

Conditions: temp:-50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of sodium methoxide (1.86 g) in DMF (30 ml) was added methyl isocyanoacetate (2.38 ml) dropwise at −50° C. and the mixture stirred for 30 min at −50° C. 2-Methylpropanoyl chloride (3.36 ml) was added gradually to the mixture at −50° C. and the mixture stirred for 2 h at −50° C. The mixture was diluted with DCM (50 ml) and saturated sodium bicarbonate solution (50 ml) was added and the organic layer collected using a hydrophobic frit. The aqueous layer was washed with DCM (2×50 ml) and separated by hydrophobic frit. The combined organic phases were concentrated in vacuo. This was purified by chromatography on silica gel, eluting with a gradient of 0-100% ethyl acetate in cyclohexane, followed by 0-20% methanol. The residue was distilled using a Kugelrohr to give the title compound (553 mg) as yellow solid. the mixture stirred for 2 h at −50° C was added the organic layer collected The aqueous layer was washed with DCM (2×50 ml) separated by hydrophobic frit The combined organic phases were concentrated in vacuo This was purified by chromatography on silica gel eluting with a gradient of 0-100% ethyl acetate in cyclohexane The residue was distilled

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

Procedure: 10-(tert-butoxycarbonyl)-13-cyclohexyl-3-methoxy-7H-indolo[2,1-a][2]benzazepine-6-carboxylic acid (1.00 g, 2.051 mmol) was dissolve in DMF (10 ml) and potassium carbonate (0.624 g, 4.51 mmol) was added to the reaction followed by methyl isocyanoacetate (0.24 ml, 2.64 mmol). The reaction was stirred under a nitrogen atmosphere at room temperature for approximately 5 minutes then cooled to 0 C. Diphenylphosphoryl azide (0.5 ml, 2.320 mmol) was slowly added to the reaction over 10 minutes. The reaction was stirred at 0 C under a nitrogen atmosphere and allowed to slowly warm to room temperature overnight. Dilute reaction with 100 ml of benzene/ethyl acetate (1:1) and wash with water. Back extract aqueous layer using ethyl acetate. Combine organic extracts and wash successively with 0.1M aqueous citric acid, saturated aqueous sodium bicarbonate and then brine and dry over magnesium sulfate. Filter and remove volatiles in vacuo. Chromatograph on 43.4 g of silica gel slurry packed in 5% ethyl acetate/dichloromethane. Elute with 5% ethyl acetate/dichloromethane. Combination of pure product fractions and removal of volatiles in vacuo yielded 215 mg of an amorphous yellow solid. Combination of less pure fractions yielded an additional 189 mg of product with purity greater than 92%. 1H NMR (500 MHz, CHLOROFORM-D) δ ppm 1.11-1.29 (m, 2H) 1.30-1.48 (m, 3H) 1.57 (s, 2H) 1.61 (s, 10H) 1.69-1.80 (m, 2H) 1.86-1.98 (m, 1H) 1.99-2.13 (m, 4H) 2.76-2.90 (m, 1H) 3.92 (s, 3H) 3.98 (s, 3H) 4.47 (d, J=12.82 Hz, 1H) 5.84 (d, J=14.65 Hz, 1H) 7.02 (d, J=2.44 Hz, 1H) 7.07 (dd, J=8.55, 2.75 Hz, 1H) 7.53 (d, J=8.55 Hz, 1H) 7.65-7.71 (m, 1H) 7.82 (d, J=8.24 Hz, 1H) 7.87 (s, 1H) 8.08 (s, 1H) 8.16 (s, 1H). LC-MS retention time 2.75 min; m/z (MH+). LC data was recorded on a Shimadzu LC-10AS liquid chromatograph equipped with a Waters Xterra MS 7u C18 3.0×50 mm column using a SPD-10AV UV-Vis detector at a detector wave length of 220 nM. The elution conditions employed a flow rate of 5 ml/min, a gradient of 100% solvent A/0% solvent B to 0% solvent A/100% solvent B, a gradient time of 3 min, a hold time of 0 min, and an analysis time of 3 min where solvent A was 5% acetonitrile/95% H2O/10 mM ammonium acetate and solvent B was 5% H2O/95% acetonitrile/10 mM ammonium acetate. MS data was determined using a Micromass Platform for LC in electrospray mode. then cooled to 0 C The reaction was stirred at 0 C under a nitrogen atmosphere to slowly warm to room temperature overnight Dilute wash with water Back extract aqueous layer Combine organic extracts and wash successively with 0.1M aqueous citric acid, saturated aqueous sodium bicarbonate brine and dry over magnesium sulfate Filter remove volatiles in vacuo Elute with 5% ethyl acetate/dichloromethane Combination of pure product fractions and removal of volatiles in vacuo

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

Procedure: 10-(tert-butoxycarbonyl)-13-cyclohexyl-3-methoxy-7H-indolo[2,1-a][2]benzazepine-6-carboxylic acid (1.00 g, 2.051 mmol) was dissolve in DMF (10 ml) and potassium carbonate (0.624 g, 4.51 mmol) was added to the reaction followed by methyl isocyanoacetate (0.24 ml, 2.64 mmol). The reaction was stirred under a nitrogen atmosphere at room temperature for approximately 5 minutes then cooled to 0 C. Diphenylphosphoryl azide (0.5 ml, 2.320 mmol) was slowly added to the reaction over 10 minutes. The reaction was stirred at 0 C under a nitrogen atmosphere and allowed to slowly warm to room temperature overnight. Dilute reaction with 100 ml of benzene/ethyl acetate (1:1) and wash with water. Back extract aqueous layer using ethyl acetate. Combine organic extracts and wash successively with 0.1M aqueous citric acid, saturated aqueous sodium bicarbonate and then brine and dry over magnesium sulfate. Filter and remove volatiles in vacuo. Chromatograph on 43.4 g of silica gel slurry packed in 5% ethyl acetate/dichloromethane. Elute with 5% ethyl acetate/dichloromethane. Combination of pure product fractions and removal of volatiles in vacuo yielded 215 mg of an amorphous yellow solid. Combination of less pure fractions yielded an additional 189 mg of product with purity greater than 92%. 1H NMR (500 MHz, CHLOROFORM-D) δ ppm 1.11-1.29 (m, 2H) 1.30-1.48 (m, 3H) 1.57 (s, 2H) 1.61 (s, 10H) 1.69-1.80 (m, 2H) 1.86-1.98 (m, 1H) 1.99-2.13 (m, 4H) 2.76-2.90 (m, 1H) 3.92 (s, 3H) 3.98 (s, 3H) 4.47 (d, J=12.82 Hz, 1H) 5.84 (d, J=14.65 Hz, 1H) 7.02 (d, J=2.44 Hz, 1H) 7.07 (dd, J=8.55, 2.75 Hz, 1H) 7.53 (d, J=8.55 Hz, 1H) 7.65-7.71 (m, 1H) 7.82 (d, J=8.24 Hz, 1H) 7.87 (s, 1H) 8.08 (s, 1H) 8.16 (s, 1H). LC-MS retention time 2.75 min; m/z (MH+). LC data was recorded on a Shimadzu LC-10AS liquid chromatograph equipped with a Waters Xterra MS 7u C18 3.0×50 mm column using a SPD-10AV UV-Vis detector at a detector wave length of 220 nM. The elution conditions employed a flow rate of 5 ml/min, a gradient of 100% solvent A/0% solvent B to 0% solvent A/100% solvent B, a gradient time of 3 min, a hold time of 0 min, and an analysis time of 3 min where solvent A was 5% acetonitrile/95% H2O/10 mM ammonium acetate and solvent B was 5% H2O/95% acetonitrile/10 mM ammonium acetate. MS data was determined using a Micromass Platform for LC in electrospray mode. then cooled to 0 C The reaction was stirred at 0 C under a nitrogen atmosphere to slowly warm to room temperature overnight Dilute wash with water Back extract aqueous layer Combine organic extracts and wash successively with 0.1M aqueous citric acid, saturated aqueous sodium bicarbonate brine and dry over magnesium sulfate Filter remove volatiles in vacuo Elute with 5% ethyl acetate/dichloromethane Combination of pure product fractions and removal of volatiles in vacuo