ethyl 2-(2-methylpropanoylamino)acetate

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

Procedure: 11.74 g of the above prepared isobutyrylamino-acetic acid ethyl ester (67.78 mmol) was dissolved in 250 ml of abs. THF and cooled down to −78°. 139 ml of 1M lithium hexamethyldisilazide in hexane (2.05 eq.) were added within 30 Min. via dropping funnel. After keeping the yellow suspension for additional 30 Min. at −78°, 6.021 ml of allyl bromide (1.05 eq.) was added and stirring continued for 15 Min. at the same temperature and for 30 Min. at 0°. Pouring of the homogeneous reaction mixture onto crashed ice/HCl, twofold extraction with AcOEt, twofold washing with water and brine, drying over magnesium sulfate, and evaporation of the solvents, followed by flash chromatography (SiO2, hexane/AcOEt=7/3) afforded. 11.70 g of the title compound as pale-yellow oil. was dissolved in 250 ml of abs at 0° Pouring of the homogeneous reaction mixture ice/HCl, twofold extraction with AcOEt twofold washing with water and brine drying over magnesium sulfate, and evaporation of the solvents afforded

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

Procedure: 10.00 g of glycine ethyl ester hydrochloride (71.6 mmol) and 21.97 ml of NEt3 (2.2 eq.) were dissolved in 200 ml of CH2Cl2 and treated between 0° and 5° dropwise with 7.81 ml of isobutyryl chloride (1.05 eq.), dissolved in 50 ml of CH2Cl2. The reaction mixture was allowed to reach ambient temperature (2.5 h) and then quenched by carefully pouring onto crashed ice/HCl/AcOEt. Separation of the layers, additional extraction of the aqueous phase with AcOEt, washing with Na2CO3 and brine, drying of the combined organic phase over magnesium sulfate, and evaporation of the solvents, followed by flash chromatography (SiO2, hexane/AcOEt=6/4) yielded 11.74 g of the title compound as colorless oil. to reach ambient temperature (2.5 h) quenched by carefully pouring Separation of the layers, additional extraction of the aqueous phase with AcOEt washing with Na2CO3 and brine drying of the combined organic phase over magnesium sulfate, and evaporation of the solvents

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

Procedure: 10.00 g of glycine ethyl ester hydrochloride (71.6 mmol) and 21.97 ml of NEt3 (2.2 eq.) were dissolved in 200 ml of CH2Cl2 and treated between 0° and 5° dropwise with 7.81 ml of isobutyryl chloride (1.05 eq.), dissolved in 50 ml of CH2Cl2. The reaction mixture was allowed to reach ambient temperature (2.5 h) and then quenched by carefully pouring onto crashed ice/HCl/AcOEt. Separation of the layers, additional extraction of the aqueous phase with AcOEt, washing with Na2CO3 and brine, drying of the combined organic phase over magnesium sulfate, and evaporation of the solvents, followed by flash chromatography (SiO2, hexane/AcOEt=6/4) yielded 11.74 g of the title compound as colorless oil. to reach ambient temperature (2.5 h) quenched by carefully pouring Separation of the layers, additional extraction of the aqueous phase with AcOEt washing with Na2CO3 and brine drying of the combined organic phase over magnesium sulfate, and evaporation of the solvents