2,3-dihydro-7-hydroxy-8-propyl-4H-1-benzopyran-4-one → 6-(5-methoxy-5-oxopentyloxy)-2-[6-[(3,4-dihydro-4-oxo-8-propyl-2H-1-benzopyran-7-yl)oxy]hexyl]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][CH2:14][CH3:15].[CH3:16][O:17][C:18](=[O:47])[CH2:19][CH2:20][C:21]1[C:26]([CH2:27][CH2:28][CH2:29][CH2:30][CH2:31][CH2:32]OS(C)(=O)=O)=[CH:25][CH:24]=[CH:23][C:22]=1[O:38][CH2:39][CH2:40][CH2:41][CH2:42][C:43]([O:45][CH3:46])=[O:44]>>[CH3:16][O:17][C:18](=[O:47])[CH2:19][CH2:20][C:21]1[C:22]([O:38][CH2:39][CH2:40][CH2:41][CH2:42][C:43]([O:45][CH3:46])=[O:44])=[CH:23][CH:24]=[CH:25][C:26]=1[CH2:27][CH2:28][CH2:29][CH2:30][CH2:31][CH2:32][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][CH2:14][CH3:15]Participants
Reactant 2
Product 1
Procedure
Using the procedure of example 11 and starting with 0.412 g (2.0 mmol) of 2,3-dihydro-7-hydroxy-8-propyl-4H-1-benzopyran-4-one and 1.0 g (2.1 mmol) of 6-[6-[(methylsulfonyl)oxy]hexyl]-2-(5-methoxy-5-oxopentyloxy)benzenepropanoic acid methyl ester, 6-(5-methoxy-5-oxopentyloxy)-2-[6-[(3,4-dihydro-4-oxo-8-propyl-2H-1-benzopyran-7-yl)oxy]hexyl]benzenepropanoic acid methyl ester was obtained in 83% yield (0.97 g) as a colorless oil. This diester (1.7 mmol) was saponified with 5 mL of 3N aqueous lithium hydroxide in 40 mL of tetrahydrofuran, at room temperature, for 20 hr. Work-up as in example 4 gave an oily acid which was flash-chromatographed on silica gel, eluting with 95:5:1 chloroform-methanol-acetic acid. There was obtained 0.76 g (81%) of pure 2-(4-carboxybutoxy)-6-[6-[(3,4-dihydro-4-oxo-8-propyl-2H-1-benzopyran-7 -yl)oxy]hexyl]benzenepropanoic acid. Recrystallization from hexane-ethyl acetate (2:1) gave 0.64 g (68%) of a colorless solid, mp 103°-104° C.
Sources & evidence
- ORD record
- ord-86b62808b6d64de68bdd5b8f5852285b
- Source dataset
- uspto-grants-1995_07
- Patent number
- US05434186
Reaction notes
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