2,3-dihydro-7-hydroxy-8-(phenylmethyl)-4H-1-benzopyran-4-one → 2-[5-[(3,4-dihydro-4-oxo-8-(phenylmethyl)-2H-1-benzopyran-7-yl)oxy]pentyloxy]benzenepropanoic acid methyl ester
Reaction equation
[OH:1][C:2]1[CH:12]=[CH:11][C:5]2[C:6](=[O:10])[CH2:7][CH2:8][O:9][C:4]=2[C:3]=1[CH2:13][C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[CH3:20][O:21][C:22](=[O:42])[CH2:23][CH2:24][C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][C:26]=1[O:31][CH2:32][CH2:33][CH2:34][CH2:35][CH2:36]OS(C)(=O)=O>>[CH3:20][O:21][C:22](=[O:42])[CH2:23][CH2:24][C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][C:26]=1[O:31][CH2:32][CH2:33][CH2:34][CH2:35][CH2:36][O:1][C:2]1[CH:12]=[CH:11][C:5]2[C:6](=[O:10])[CH2:7][CH2:8][O:9][C:4]=2[C:3]=1[CH2:13][C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1Participants
Reactant 2
Product 1
Procedure
Using the procedure of example 11 and starting with 1.2 g (4.72 mmol) of 2,3-dihydro-7-hydroxy-8-(phenylmethyl)-4H-1-benzopyran-4-one (from example 70) and 1.64 g (4.76 mmol) of 2-[[5-[(methylsulfonyl)oxy]pentyl]oxy]benzenepropanoic acid methyl ester (from example 72), 2-[5-[(3,4-dihydro-4-oxo-8-(phenylmethyl)-2H-1 -benzopyran-7-yl)oxy]pentyloxy]benzenepropanoic acid methyl ester was obtained in 91.5% yield (2.17 g) as a yellow oil. This diester (4.32 mmol) was saponified with 6.5 mL of 3N aqueous lithium hydroxide in 21 mL of tetrahydrofuran, at room temperature, for 48 hr. Work-up as in example 4 gave 2-[5-[(3,4-dihydro-4-oxo-8-(phenylmethyl)-2H-1-benzopyran-7-yl)oxy]pentyloxy]benzenepropanoic acid as an oil. This material was flash chromatographed on silica gel eluting with ethyl acetate-hexane mixtures giving 1.0 g (47.6%) of pure acid as a solid. Recrystallization from ethyl acetate-ether gave a colorless solid, mp 117°-118° C.
Sources & evidence
- ORD record
- ord-5a61521810e14a04967dd5fa70a0aef8
- Source dataset
- uspto-grants-1995_07
- Patent number
- US05434186
Reaction notes
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