Resorcinol → 4-(chloromethyl)-7-hydroxy-2H-chromen-2-one

HRID 2364897Notes

Reaction equation

HRID 2364897 reaction equation
[Cl:1][CH2:2][C:3](=O)[CH2:4][C:5]([O:7][CH2:8][CH3:9])=[O:6].[C:11]1([CH:18]=CC=[C:14](O)[CH:13]=1)[OH:12]>OS(O)(=O)=O>[Cl:1][CH2:2][C:3]1[C:9]2[C:8](=[CH:18][C:11]([OH:12])=[CH:13][CH:14]=2)[O:7][C:5](=[O:6])[CH:4]=1

Participants

4

Reactant 2

HCID 5054ResorcinolHCID 69484Ethyl 4-chloroacetoacetate

Product 1

HCID 53988464-(chloromethyl)-7-hydroxy-2H-chromen-2-oneYield 79.4%

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Procedure

Ethyl 4-chloroacetoacetate (10.0 mL, 73.0 mmol) was added dropwise to a cold (ice bath) solution of resorcinol (8.0 g, 73.0 mmol) in concentrated H2SO4 (100 mL). The cooling bath was removed, and the reaction mixture was stirred at room temperature overnight (15 h), then poured onto ice (500 mL) and stirred until all ice had melted. The precipitate was collected by filtration and washed with water (200 mL). The solid was dissolved in hot EtOH:ligroin (4:1, 100 mL), filtered, and the filtrate was kept in the freezer (−20° C.) for 3 h. The solid was collected by filtration, washed with ligroin (3×10 mL), and dried to give 4-Chloromethyl-7-hydroxy-2H-chromen-2-one (1) as a pale white solid (12.2 g, 79%).

Workup

  1. customThe cooling bath was removed
  2. additionpoured onto ice (500 mL)
  3. stirringstirred until all ice
  4. filtrationThe precipitate was collected by filtration
  5. washwashed with water (200 mL)
  6. dissolutionThe solid was dissolved in hot EtOH:ligroin (4:1, 100 mL)
  7. filtrationfiltered
  8. waitthe filtrate was kept in the freezer (−20° C.) for 3 h
  9. filtrationThe solid was collected by filtration
  10. washwashed with ligroin (3×10 mL)
  11. customdried

Sources & evidence

ORD record
ord-22c4d4c8b8d74c90b29b681c76b29159
Source dataset
uspto-grants-2014_04
Patent number
US08697109B2

Reaction notes

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