Methanol → (+)-3-(6-Hydroxychroman-3-ylmethyl)benzoic acid methyl ester

HRID 1684634Notes

Reaction equation

HRID 1684634 reaction equation
[CH3:1][O:2][C:3](=[O:23])[C:4]1[CH:9]=[CH:8][CH:7]=[C:6]([CH2:10][C@H:11]2[C@@H:20](O)[C:19]3[C:14](=[CH:15][CH:16]=[C:17]([OH:22])[CH:18]=3)[O:13][CH2:12]2)[CH:5]=1.[H][H].CO>C(O)(=O)C.ClCCl.[OH-].[Pd+2].[OH-]>[CH3:1][O:2][C:3](=[O:23])[C:4]1[CH:9]=[CH:8][CH:7]=[C:6]([CH2:10][CH:11]2[CH2:20][C:19]3[C:14](=[CH:15][CH:16]=[C:17]([OH:22])[CH:18]=3)[O:13][CH2:12]2)[CH:5]=1

Participants

7

Reactant 3

HCID 887MethanolHCID 53958213(3R-cis)-3-(4,6-dihydroxychroman-3-ylmethyl)benzoic acid methyl esterHCID 178418361HCID 178418361, compound

Product 1

HCID 54437409(+)-3-(6-Hydroxychroman-3-ylmethyl)benzoic acid methyl esterYield 81%

Reagents, catalysts & solvents 3

HCID 9942167Palladium hydroxideCatalystHCID 176Acetic AcidSolventHCID 6344DichloromethaneSolvent

Procedure

A mixture of 5.0 g (0.017 mole) of (3R-cis)-3-(4,6-dihydroxychroman-3-ylmethyl)benzoic acid methyl ester (prepared by esterification of the corresponding carboxylic acid (prepared according to the method of co-pending U.S. Pat. Application of Murtiashaw, et al., U.S. Ser. No. 07/964,336 filed Oct. 21, 1992) and 1.0 g palladium hydroxide in 100 mL glacial acetic acid was shaken in a Parr hydrogenator under 50 psi hydrogen at room temperature for 3 hours. The mixture was filtered through Celite and the filtrate concentrated to give an oil. Flash chromatography on silica gel eluting with 5% methanol in dichloromethane yielded 4.3 g (81% of the title product as an oil). NMR (CDCl3): δ2.30 (m, 1H); 2.50 (dd, 1 ,H) ; 2.75 (m, 3H); 3.80 (dd, 1H); 3.92 (s, 3H); 4.15 (dd, 1H). MS (Cl, NH3) m/e: 316 (100).

Workup

  1. customprepared
  2. filtrationThe mixture was filtered through Celite
  3. concentrationthe filtrate concentrated
  4. customto give an oil

Sources & evidence

ORD record
ord-78d13f089dc44125a7e5e5f11112b2ef
Source dataset
uspto-grants-1997_06
Patent number
US05641789

Reaction notes

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