Iodine → 2-Chloro-5-iodobenzyl alcohol

HRID 718209Notes

Reaction equation

HRID 718209 reaction equation
[BH4-].[Na+].II.[Cl:5][C:6]1[CH:14]=[CH:13][C:12]([I:15])=[CH:11][C:7]=1[C:8](O)=[O:9].CC(=O)OCC>C1COCC1>[Cl:5][C:6]1[CH:14]=[CH:13][C:12]([I:15])=[CH:11][C:7]=1[CH2:8][OH:9]

Participants

6

Procedure

A 250 mL of 4-necked flask equipped with thermometer and mechanical stirring was charged with NaBH4 (4.16 g, 0.11 mol) and THF (60 mL) under argon. After cooling to 0˜5° C. with stirring, a solution of iodine in THF (12.7 g I2 in 25 mL THF) was added slowly dropwise over 30 min and the reaction temperature was maintained below 10° C. After the addition was completed, a solution of 2-chloro-5-iodobenzoic acid (15.0 g, 50 mmol) in THF (20 mL) was added dropwise over 30 min and kept the reaction temperature below 10° C. After stirring for another 3 h at 20˜25° C., the reaction mixture was heated to reflux for additional 16 h and monitored by TLC (PE/EA=1:1, Rf=0.2). The mixture was cooled to 20˜25° C. and poured into ice water (100 mL), extracted with ethyl acetate (2×100 mL), washed with water (2×100 mL), brine (100 mL), concentrated and the residue was purified by flash chromatography (PE:EA=20:1 as eluant, 200 mL) to give an off-white solid. Yield: 10.0 g (70%) MS ESI (m/z): 269 [M+1]+.

Workup

  1. customA 250 mL of 4-necked flask equipped with thermometer
  2. temperatureAfter cooling to 0˜5° C.
  3. stirringwith stirring
  4. temperaturethe reaction temperature was maintained below 10° C
  5. additionAfter the addition
  6. customthe reaction temperature below 10° C
  7. stirringAfter stirring for another 3 h at 20˜25° C.
  8. temperaturethe reaction mixture was heated
  9. temperatureto reflux for additional 16 h
  10. temperatureThe mixture was cooled to 20˜25° C.
  11. extractionextracted with ethyl acetate (2×100 mL)
  12. washwashed with water (2×100 mL), brine (100 mL)
  13. concentrationconcentrated
  14. customthe residue was purified by flash chromatography (PE:EA=20:1 as eluant, 200 mL)
  15. customto give an off-white solid

Sources & evidence

ORD record
ord-3d703b526b42451c8ad0996b375aa0c0
Source dataset
uspto-grants-2015_11
Patent number
US09193751B2

Reaction notes

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