Water → 6-Chloro-7-methoxy-2-methylchroman-4-one
Reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([OH:8])=[CH:4][C:3]=1[O:9][CH3:10].[C:11](O)(=[O:15])/[CH:12]=[CH:13]/[CH3:14].O>CS(O)(=O)=O>[Cl:1][C:2]1[CH:7]=[C:6]2[C:5](=[CH:4][C:3]=1[O:9][CH3:10])[O:8][CH:13]([CH3:14])[CH2:12][C:11]2=[O:15]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 23 °C
Procedure
A solution of 1.0 g (6.3 mmol) 4-chloro-3-methoxyphenol and 5.4 g (6.3 mmol) crotonic acid in 15 ml methane sulfonic acid was heated at 95° C. under nitrogen for 20 hours. The reaction was cooled to 23° C., poured onto 150 ml ice and water and extracted with 100 ml ethyl acetate. The ethyl acetate extract was successively washed with 100 ml water, 2×100 ml 1N sodium hydroxide and 100 ml brine, dried over magnesium sulfate and concentrated in vacuo to a purple crystalline solid. This was purified by flash chromatography on 150 cc silica gel using chloroform as eluant to give the product as a yellow crystalline solid, 1.1 g (78%); m.p. 96°-100° C.
Workup
- extractionextracted with 100 ml ethyl acetate
- extractionThe ethyl acetate extract
- washwas successively washed with 100 ml water, 2×100 ml 1N sodium hydroxide and 100 ml brine
- dry with materialdried over magnesium sulfate
- concentrationconcentrated in vacuo to a purple crystalline solid
- customThis was purified by flash chromatography on 150 cc silica gel
Sources & evidence
- ORD record
- ord-21c18e9709a14f81b62fa461359a85c9
- Source dataset
- uspto-grants-1989_08
- Patent number
- US04853410
Reaction notes
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