tert-butyl N-(1-oxobutan-2-yl)carbamate

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: Method C was followed, using 5-(6-chloro-9H-β-carbolin-8-ylcarbamoyl)-2,2-dimethyl-morpholine-4-carboxylic acid tert-butyl ester and the appropriate aldehyde, (1-formyl-propyl)-carbamic acid tert-butyl ester.

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

Procedure: Method C was followed, using 5-(6-chloro-9H-β-carbolin-8-ylcarbamoyl)-2,2-dimethyl-morpholine-4-carboxylic acid tert-butyl ester and the appropriate aldehyde, (1-formyl-propyl)-carbamic acid tert-butyl ester.

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: Method C was followed, using 5-(6-chloro-9H-β-carbolin-8-ylcarbamoyl)-2,2-dimethyl-morpholine-4-carboxylic acid tert-butyl ester and the appropriate aldehyde, (1-formyl-propyl)-carbamic acid tert-butyl ester.

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 2-cyclopropyl-[1,3,4]oxadiazole (2.16 g, 19.6 mmol) in dry THF (100 mL) is cooled to −78° C. nBuLi (1.6M in hexanes, 12.3 mL, 19.6 mmol) is added dropwise. The reaction mixture is stirred at −78° C. for 40 min. MgBr2.OEt2 (5.0692 g, 19.6 mmol) is added. The reaction mixture is allowed to warm up to −45° C. and stirred at that temperature for 1.5 hr. A solution of (1-formyl-propyl)-carbamic acid tert-butyl ester (3.7 g, 19.6 mmol) in THF (40 mL) is added. The reaction mixture is allowed to warm up to −20° C. and stirred at that temperature for 3.5 hrs. The reaction mixture is quenched with a solution of saturated NH4Cl solution and extracted with ethyl acetate. Combined organic extracts is washed with saturated NaCl solution and dried over MgSO4. The solvent is evaporated under reduced pressure and the crude is purified by column chromatography eluting with ethyl acetate and heptane mixture to give {1-[(5-cyclopropyl-[1,3,4]oxadiazol-2-yl)-hydroxy-methyl]-propyl}-carbamic acid tert-butyl ester (2.83 g, 49%). is added dropwise to warm up to −45° C. stirred at that temperature for 1.5 hr to warm up to −20° C. stirred at that temperature for 3.5 hrs The reaction mixture is quenched with a solution of saturated NH4Cl solution extracted with ethyl acetate Combined organic extracts is washed with saturated NaCl solution dried over MgSO4 The solvent is evaporated under reduced pressure the crude is purified by column chromatography eluting with ethyl acetate and heptane mixture

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

Procedure: To a solution of 5-thiophen-2-yl-oxazole (0.85 g, 5.62 mmol) in dry THF (4 mL) is added triethylborane (1.0 M in THF, 5.62 mmol, 5.62 mL). The mixture is stirred at room temperature for 45 min, then cooled to −78° C. and n-butyl lithium (1.6 M in hexane, 5.62 mmol, 3.51 mL) is added drop wise. The mixture is stirred at −78° C. for 45 min then a solution of (1-Formyl-propyl)-carbamic acid tert-butyl ester (2.81 mmol, 0.526 g) in dry THF (3 mL) is added slowly. The mixture is stirred at −78° C. for 4 h, then warmed to 0° C. and quenched by adding 30 mL of 10% (vol) HOAc in ethanol. The mixture is stirred at room temperature for 18 hr and then concentrated in vacuum. The residue is purified over 90 g of silica gel, eluted with ethyl acetate: heptane (1:2 then 1:1) to afford {(S)-1-[hydroxy-(5-thiophen-2-yl-oxazol-2-yl)-methyl]-propyl}-carbamic acid tert-butyl ester (363 mg, 38%) as an oil. cooled to −78° C. The mixture is stirred at −78° C. for 45 min The mixture is stirred at −78° C. for 4 h warmed to 0° C. quenched by adding 30 mL of 10% (vol) HOAc in ethanol The mixture is stirred at room temperature for 18 hr concentrated in vacuum The residue is purified over 90 g of silica gel eluted with ethyl acetate: heptane (1:2