Benzophenone → 4-METHOXY-2'-METHYLBENZOPHENONE

HRID 974115Notes

Reaction equation

HRID 974115 reaction equation
[C:1]1([CH3:10])[C:2]([C:7](Cl)=[O:8])=[CH:3][CH:4]=[CH:5][CH:6]=1.[C:11]1([O:17][CH3:18])[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.C(C1C=CC=CC=1)(=O)C1C=CC=CC=1.C(O)C#C.C1C2C(=CC=CC=2)C=CC=1O.C1(C)C=CC(S(O)(=O)=O)=CC=1.[OH-].[Na+]>[Cl-].[Al+3].[Cl-].[Cl-].C1C=CC=CC=1.C(=S)=S>[CH3:10][C:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[C:7]([C:14]1[CH:15]=[CH:16][C:11]([O:17][CH3:18])=[CH:12][CH:13]=1)=[O:8]

Participants

11

Reactant 7

HCID 3102BenzophenoneHCID 6101p-Toluenesulfonic acidHCID 7519AnisoleHCID 7859Propargyl alcoholHCID 86632-NaphtholHCID 14798Sodium HydroxideHCID 702762-Methylbenzoyl chloride

Product 1

HCID 6145214-METHOXY-2'-METHYLBENZOPHENONE

Reagents, catalysts & solvents 3

HCID 6451240Aluminum(III) ChlorideCatalystHCID 241BenzeneSolventHCID 6348Carbon DisulfideSolvent

Procedure

2-methyl-4'-methoxybenzophenone was prepared by the Friedel-Crafts reaction of ortho-toluoyl chloride and anisole using aluminum chloride as a catalyst and carbon disulfide as the solvent. 11.1 grams (0.05 mole) of the resulting benzophenone was converted to the propargyl alcohol using the method described in Example 1, Step 2. The crude product was mixed with 6 grams of 2-naphthol and 0.1 gram of p-toluene sulfonic acid in 200 milliliters of benzene and the mixture stirred overnight at room temperature. The resultant reaction mixture was poured into an equal volume of aqueous 5 percent sodium hydroxide to remove unreacted naphthol. The organic layer was washed with water and the benzene solvent removed on a rotary evaporator. The resulting oil residue was column chromatographed on silica using a 1:1 mixture of chloroform and hexane as elutant. The photochromic fractions were combined and the product crystallized from a mixture of hexane and diethyl ether. The product (4.8 grams) had a melting range of 131-133° C. NMR analysis of the product confirmed it to be 3(2-methylphenyl)-3-(4-methoxyphenyl)-3H-naphtho[2,1-b]pyran.

Workup

  1. customThe resultant reaction mixture
  2. customto remove unreacted naphthol
  3. washThe organic layer was washed with water
  4. customthe benzene solvent removed on a rotary evaporator
  5. customchromatographed on silica using
  6. additiona 1:1 mixture of chloroform and hexane as elutant
  7. customthe product crystallized from a mixture of hexane and diethyl ether

Sources & evidence

ORD record
ord-23ce97f8a6c34ef38d305bc406ed1cf2
Source dataset
uspto-grants-1991_11
Patent number
US05066818

Reaction notes

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