Sulfuric Acid → Dibenzoylmethane

HRID 2051050Notes

Reaction equation

[C:1]([C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1)(=[O:3])[CH3:2].C[O:11][C:12](=O)[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1.C[O-].[Na+].S(=O)(=O)(O)O>O.CO.C1(C)C(C)=CC=CC=1>[C:1]([CH2:2][C:12](=[O:11])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)(=[O:3])[C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1

Participants

Conditions

Temperature: 130 °C

Procedure

Acetophenone (30 grams; 0.25 mol), methylbenzoate (130 grams, 1.0 mol), sodium methoxide (17.3 grams; 0.32 mol) and xylene (350 ml) were placed into a four necked round bottom one liter flask, equipped with stirrer, nitrogen addition adapter, thermometer and Oldershaw column connected with a distillation head and a trap. The solution was heated under a blanket of nitrogen to a temperature of about 130° C. At about 130° C., the mixture of xylene and methanol begins to come off the reaction mixture. Upon cooling the reaction mixture is acidified by adding sulfuric acid (21 ml) in water (100 ml). Once the material goes into solution it is transferred to a separatory funnel and the aqueous layer is removed. The xylene layer is washed with water (100 ml of a 10% solution). Then it is stirred at 120° C. and 15 mm Hg. The yield of dibenzoyl methane was 94 weight percent having a purity of 97%.

Workup

customequipped with stirrer, nitrogen addition adapter
temperatureUpon cooling the reaction mixture
customis transferred to a separatory funnel
customthe aqueous layer is removed
washThe xylene layer is washed with water (100 ml of a 10% solution)

Sources & evidence

ORD record: ord-7788080cf25b4f609be006a4471edc2e
Source dataset: uspto-grants-1991_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05015777

Reaction notes

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