Dichloromethane → (+)-L-Leucine methyl ester

HRID 1089823Notes

Reaction equation

HRID 1089823 reaction equation
Cl.[CH3:2][O:3][C:4](=[O:11])[C@H:5]([CH2:7][CH:8]([CH3:10])[CH3:9])[NH2:6].C(=O)(O)[O-].[Na+].C(Cl)Cl>O1CCOCC1.CCCCCC.CCOC(C)=O>[CH3:2][O:3][C:4](=[O:11])[C@H:5]([CH2:7][CH:8]([CH3:10])[CH3:9])[NH2:6]

Participants

7

Reactant 3

HCID 6344DichloromethaneHCID 516892Sodium BicarbonateHCID 2723695Leucine methyl ester hydrochloride

Product 1

HCID 65105(+)-L-Leucine methyl esterYield 79.3%

Reagents, catalysts & solvents 3

HCID 8058HexaneSolventHCID 8857Ethyl AcetateSolvent2×HCID 312751,4-DioxaneSolvent

Procedure

A suspension of L-leucine methyl ester hydrochloride (3.0 g, 16.5 mmol) and sodium bicarbonate (large excess) in 30 mL of dioxane was charged with 9-fluorenemethoxycarbonyl-O-succinimide (2.5 g, 7.43 mmol) at room temperature. The reaction was monitored via TLC (silica, 25% EtOAc in hexane). After two hours 30 ml of methylene chloride was introduced and the reaction was stirred at room temperature for 48 hours. The solution was diluted with EtOAc, washed with water (×2), 3% aqueous HCl, water (×3) and brine. The solution was dried over magnesium sulfate and evaporated. The resulting oil was crystalized from hexane:ether to yield 1.9 g (62%) of colorless solid.

Workup

  1. washwashed with water (×2), 3% aqueous HCl, water (×3) and brine
  2. dry with materialThe solution was dried over magnesium sulfate
  3. customevaporated
  4. customThe resulting oil was crystalized from hexane

Sources & evidence

ORD record
ord-971a03a211b642218579015e72502d89
Source dataset
uspto-grants-1992_01
Patent number
US05079260

Reaction notes

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