Reaction #1790

Reaction equation

N-Boc-trans-1-amino-4-cyclohexanol

diethyl azodicarboxylate

methyl 4-hydroxy-2-methoxybenzoate

triphenylphosphine

→

methyl 4-[N-Boc-cis-1-amino-4-cyclohexanoyloxy]-2-methoxybenzoate

Solvents

THF

THF

Conditions

Workup

1. 1
   FiltrationThe reaction was filtered
2. 2
   Otherthe solvent was removed under reduced pressure
3. 3
   OtherThe residue was chromatographed on a silica gel column
4. 4
   WashEtOAc and eluted with same
5. 5
   Otherthe solvent removed under reduced pressure

Procedure

To a stirred solution of methyl 4-hydroxy-2-methoxybenzoate (1.09 g, 6.0 mmol) in dry THF (7 mL) was added triphenylphosphine (1.57 g, 6.0 mmol) and the solution was cooled to 0° C. A 4.0 mL volume of N-Boc-trans-1-amino-4-cyclohexanol (1 g, 4.0 mmol) and diethyl azodicarboxylate (945 μL, 6.0 mmol) in THF was added dropwise via addition funnel over 0.5 h. The reaction was filtered and the solvent was removed under reduced pressure. The residue was chromatographed on a silica gel column packed in 70:30 hexanes:EtOAc and eluted with same. The appropriate fractions were combined and the solvent removed under reduced pressure to afford methyl 4-[N-Boc-cis-1-amino-4-cyclohexanoyloxy]-2-methoxybenzoate.

Source