Citric Acid → 1,2-dibenzyl 1-tert.butyl 1-(3-hydroxypropyl)-4-methyl-1,1,2(R)-pentanetricarboxylate

HRID 1464364Notes

Reaction equation

HRID 1464364 reaction equation
[CH3:1][CH:2]([CH3:36])[CH2:3][C@@H:4]([C:26]([O:28][CH2:29][C:30]1[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=1)=[O:27])[C:5]([CH2:23][CH:24]=[CH2:25])([C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])[C:6]([O:8][CH2:9][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)=[O:7].[OH-].[Na+].OO.C(O)(=O)CC(CC(O)=O)(C(O)=O)[OH:44]>C(OCC)C.O>[OH:44][CH2:25][CH2:24][CH2:23][C:5]([C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])([C:6]([O:8][CH2:9][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)=[O:7])[C@H:4]([C:26]([O:28][CH2:29][C:30]1[CH:31]=[CH:32][CH:33]=[CH:34][CH:35]=1)=[O:27])[CH2:3][CH:2]([CH3:36])[CH3:1]

Participants

7

Reactant 4

HCID 311Citric AcidHCID 784Hydrogen PeroxideHCID 14798Sodium HydroxideHCID 678262121,2-dibenzyl 1-tert.butyl 4-methyl-1-(prop-2-en-1yl)-1,1,2(R)-pentanetricarboxylate

Product 1

HCID 678262341,2-dibenzyl 1-tert.butyl 1-(3-hydroxypropyl)-4-methyl-1,1,2(R)-pentanetricarboxylate

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent

Procedure

A solution of 2.47 g of 1,2-dibenzyl 1-tert.butyl 4-methyl-1-(prop-2-en-1-yl)-1,1,2(R)-pentanetricarboxylate in 5 ml of dry diethyl ether was cooled to 0° and 0.325 ml of monochloroborane-methyl sulphide complex was added. The mixture was stirred at room temperature for 2 hours, then cooled to 0° and 0.5 ml of water, 2.3 ml of 1.5M aqueous sodium hydroxide solution and 2.3 ml of 30% aqueous hydrogen peroxide were added. The mixture was stirred at room temperature for 3 hours and then acidified with 5% aqueous citric acid solution. The product was extracted with diethyl ether and the extract was washed with saturated sodium chloride solution, dried over anhydrous magnesium sulfate and evaporated. The residue was purified by flash chromatography on silica gel using hexane/ethyl acetate (5:1) for the elution. There were obtained 1.098 g of 1,2-dibenzyl 1-tert.butyl 1-(3-hydroxypropyl)-4-methyl-1,1,2(R)-pentanetricarboxylate in the form of a colorless oil; MS: 513 (M+H)+.

Workup

  1. addition0.325 ml of monochloroborane-methyl sulphide complex was added
  2. temperaturecooled to 0°
  3. stirringThe mixture was stirred at room temperature for 3 hours
  4. extractionThe product was extracted with diethyl ether
  5. washthe extract was washed with saturated sodium chloride solution
  6. dry with materialdried over anhydrous magnesium sulfate
  7. customevaporated
  8. customThe residue was purified by flash chromatography on silica gel
  9. washfor the elution

Sources & evidence

ORD record
ord-6f33401707de4d2fb95026dc61934c1d
Source dataset
uspto-grants-1994_04
Patent number
US05304549

Reaction notes

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