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

HRID 1290556Notes

Reaction equation

HRID 1290556 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 stirred for 20 hours. The mixture was washed in turn with water and 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-toluenesulphonyloxy)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 dilute aqueous sodium carbonate solution
  2. filtrationThe organic solution was filtered through phase
  3. customseparating paper
  4. customevaporated

Sources & evidence

ORD record
ord-9622c371e17141ea9a234d4f57043ab4
Source dataset
uspto-grants-1998_05
Patent number
US05750754

Reaction notes

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