4-Toluenesulfonyl chloride → tert-butyl (3R)-3-methyl-4-(p-toluenesulphonyloxy)butyrate

HRID 266772Notes

Reaction equation

HRID 266772 reaction equation
[C:1]1([CH3:11])[CH:6]=[CH:5][C:4]([S:7](Cl)(=[O:9])=[O:8])=[CH:3][CH:2]=1.[OH:12][CH2:13][C@H:14]([CH3:23])[CH2:15][C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17].C(N(CC)CC)C>ClCCl>[CH3:23][C@@H:14]([CH2:13][O:12][S:7]([C:4]1[CH:5]=[CH:6][C:1]([CH3:11])=[CH:2][CH:3]=1)(=[O:9])=[O:8])[CH2:15][C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17]

Participants

5

Reactant 3

HCID 73974-Toluenesulfonyl chlorideHCID 8471TriethylamineHCID 107259131,1-Dimethylethyl (3R)-4-hydroxy-3-methylbutanoate

Product 1

HCID 53813491tert-butyl (3R)-3-methyl-4-(p-toluenesulphonyloxy)butyrateYield 96.5%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

p-Toluenesulphonyl chloride (13.2 g) was added portionwise to a stirred mixture of tert-butyl (3R)-4-hydroxy-3-methylbutyrate (11 g), triethylamine (21 ml) and dichloromethane (120 ml) and the mixture was stirred at room temperature for 20 hours. The mixture was washed in turn with water and with a dilute aqueous sodium carbonate solution. The organic solution was filtered through phase separating paper and evaporated to give tert-butyl (3R)-3-methyl-4-(p-toiuenesulphonyloxy)-butyrate as an oil (20 g): NMR(CDCl3) δ 7.6(2H,d), 7.33(2H,d), 3.92(2H,d), 2.45(3H,s), 2.18-2.47(2H,m), 2.0-2.15(1H,m), 1.42(9H,s), 0.95(3H,d).

Workup

  1. washThe mixture was washed in turn with water and with a dilute aqueous sodium carbonate solution
  2. filtrationThe organic solution was filtered through phase
  3. customseparating paper
  4. customevaporated

Sources & evidence

ORD record
ord-947007fd631b45f9ad01ecc161a60e30
Source dataset
uspto-grants-1997_07
Patent number
US05652242

Reaction notes

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