Methyl iodide → 7-methoxy-2,2-dimethyl-3,4-dihydro-2H-1-benzopyran-4-one

HRID 1073373Notes

Reaction equation

HRID 1073373 reaction equation
[OH-].[Na+].[CH3:3]I.[OH:5][C:6]1[CH:15]=[C:14]2[C:9]([C:10](=[O:18])[CH2:11][C:12]([CH3:17])([CH3:16])[O:13]2)=[CH:8][CH:7]=1>ClCCl.[Cl-].C([N+](CC)(CC)CC1C=CC=CC=1)C>[CH3:3][O:5][C:6]1[CH:15]=[C:14]2[C:9]([C:10](=[O:18])[CH2:11][C:12]([CH3:16])([CH3:17])[O:13]2)=[CH:8][CH:7]=1

Participants

6

Reactant 3

HCID 6328Methyl iodideHCID 14798Sodium HydroxideHCID 6009027-hydroxy-2,2-dimethyl-3,4-dihydro-2H-1-benzopyran-4-one

Product 1

HCID 6056607-methoxy-2,2-dimethyl-3,4-dihydro-2H-1-benzopyran-4-oneYield 94.6%

Reagents, catalysts & solvents 2

HCID 66133Benzyl triethylammonium chlorideCatalystHCID 6344DichloromethaneSolvent

Procedure

In 40 ml of 5% sodium hydroxide solution 3.84 g (20 millimoles) of 7-hydroxy-2,2-dimethyl-4-chromanone are dissolved whereupon 80 ml of dichloro methane and 0.5 g of triethyl benzyl ammonium chloride are added and the mixture is intensively stirred at room temperature for 20 minutes. After addition of 4.25 g (1.9 ml, 30 millimole) of methyl iodide the reaction mixture is stirred for 2 hours. The organic layer is separated, washed twice with 50 ml of water each, dried over sodium sulfate and evaporated. The residue is crystallized from 80% methanol. Thus 3.9 g of the desired compound are obtained, yield 94.6%. Mp. 77°-78° C.

Workup

  1. additionare added
  2. stirringis stirred for 2 hours
  3. customThe organic layer is separated
  4. washwashed twice with 50 ml of water each,
  5. dry with materialdried over sodium sulfate
  6. customevaporated
  7. customThe residue is crystallized from 80% methanol

Sources & evidence

ORD record
ord-203c894565c44cea8216ecababa35044
Source dataset
uspto-grants-1990_11
Patent number
US04968819

Reaction notes

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