tert-Butanol → (R)-2-(4-isobutylphenyl)-1,2-propanediol

HRID 37017Notes

Reaction equation

HRID 37017 reaction equation
OP([O-])(O)=O.[K+].[CH3:7][C:8]([OH:11])([CH3:10])[CH3:9].C([O-])([O-])=[O:13].[K+].[K+].[CH2:18]([C:22]1[CH:27]=[CH:26]C(C(C)=C)=[CH:24][CH:23]=1)[CH:19]([CH3:21])[CH3:20]>O=[Os](=O)(=O)=O.O>[CH2:18]([C:22]1[CH:27]=[CH:26][C:7]([C@:8]([OH:11])([CH3:10])[CH2:9][OH:13])=[CH:24][CH:23]=1)[CH:19]([CH3:21])[CH3:20]

Participants

7

Reactant 4

HCID 6386tert-ButanolHCID 11430Potassium CarbonateHCID 516951Monobasic potassium phosphateHCID 10176333Benzene, 1-(1-methylethenyl)-4-(2-methylpropyl)-

Product 1

HCID 9837184(R)-2-(4-isobutylphenyl)-1,2-propanediolYield 100%

Reagents, catalysts & solvents 2

HCID 30318Osmium TetroxideCatalystHCID 962WaterSolvent

Procedure

The cathode compartment of the above described glass H-cell is charged with an aqueous solution of KH2PO4 (0.4M, 50 mL) and the anode is charged with the following: t-BuOH (50 mL), H2O (50 mL), K2CO3 (2.65 g, 20 mmol), K4Fe(CN)6.3H2O(0.633 g, 1.5 mmol). The solution is kept at 22° C. and the electrolysis is commenced at a controlled potential of 0.20-0.25 V (vs reference Ag/AgCl). After ca. 144 coulombs of electricity is consumed, the anode compartment is charged with the chiral ligand, MEQ-DHQD, (94 mg, 0.2 mmol), OsO4 in toulene (0.1 mL, 0.196M) and 2-(4-isobutylphenyl)propene (0.45 g, 2.5 mmol). After a total of 448 coulombs of electricity is further consumed, the reaction is stopped and is worked up as above to give the diol, (R)-2-(4-isobutylphenyl)-1,2-propanediol, in ca. 100% yield and 81.4% ee (crude ee by HPLC analysis on the chiracel OJ column).

Workup

  1. customis kept at 22° C.
  2. customAfter ca. 144 coulombs of electricity is consumed
  3. customAfter a total of 448 coulombs of electricity is further consumed

Sources & evidence

ORD record
ord-ca39d17f0dc64e1892531ac59002b01b
Source dataset
uspto-grants-1995_05
Patent number
US05419817

Reaction notes

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