Reaction #51637

ord-6df9962d8c7b408d88e338c40f53bfc4

Reaction equation

CC(=O)OC(C)=O
acetic anhydride
COc1cc2c(cc1O)CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H]1CCC21OCCO1
ketal
COc1cc2c(cc1O)CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H]1CCC21OCCO1
17,17-Ethylenedioxy-2-methoxyestra-1,3,5(10)-trien-3-ol
c1ccncc1
pyridine
→
COc1cc2c(cc1OC(C)=O)CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H]1CCC21OCCO1
3-acetate
Yield 96.1%
COc1cc2c(cc1OC(C)=O)CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H]1CCC21OCCO1
17,17-Ethylenedioxy-2-methoxyestra-1,3,5(10)-trien-3-ol Acetate
Yield 96.1%

Reactants

CC(=O)OC(C)=O
acetic anhydride
COc1cc2c(cc1O)CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H]1CCC21OCCO1
ketal
COc1cc2c(cc1O)CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H]1CCC21OCCO1
17,17-Ethylenedioxy-2-methoxyestra-1,3,5(10)-trien-3-ol
c1ccncc1
pyridine

Reagents

None

Solvents

CO
methanol

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    Othersolvents removed in vacuo
  2. 2
    Otherthe residue obtained
  3. 3
    Othercrystallized from methanol

Procedure

Under nitrogen, acetic anhydride (25 mL, 265 mmol) was added to a solution of the ketal (11) (4.5 g, 13.06 mmol) in dry pyridine (25 mL, 310 mmol). The reaction was stirred overnight at room temperature in the dark. After that time, methanol (50 mL) was added and solvents removed in vacuo. The treatment with methanol was repeated and the residue obtained crystallized from methanol to give the pure 3-acetate (12) (4.85 g, 96%).

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US06852710B2uspto-grants-2005_02