Reaction #69130

Reaction equation

Trans-tert-butyl (R)-1-(4-aminocyclohexyl)ethylcarbamate

D-Lactic Acid

diisopropylethylamine

TBTU

→

title compound

Yield 41.0%

Trans-tert-butyl (R)-1-(4-((R)-2-hydroxypropanamido)cyclohexyl)ethylcarbamate

Yield 41.0%

Solvents

DMF

Conditions

Workup

1. 1
   OtherThe crude mixture was partitioned between ethyl acetate and brine
2. 2
   DryingThe organic extracts were dried over magnesium sulfate
3. 3
   Filtrationfiltered
4. 4
   Concentrationconcentrated in vacuo
5. 5
   OtherThe residue was purified on silica gel by column chromatography (ISCO Companion, 12 g column, 0-10% MeOH/DCM)

Procedure

Trans-tert-butyl (R)-1-(4-aminocyclohexyl)ethylcarbamate (125 mg, 0.52 mmol) was dissolved in DMF (3 mL). D-Lactic Acid (49.52 mg, 0.52 mmol), diisopropylethylamine (166.6 mg, 224.5 μL, 1.29 mmol) and TBTU (165.6 mg, 0.5158 mmol) were successively added. The reaction mixture was allowed to stir at ambient temperature for 3 hours. The crude mixture was partitioned between ethyl acetate and brine. The organic extracts were dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was purified on silica gel by column chromatography (ISCO Companion, 12 g column, 0-10% MeOH/DCM) to afford the title compound (66.1 mg, 41% yield).

Source