Diisopropylethylamine → benzyl N-(2-oxoethyl)carbamate

HRID 600638

Reaction equation

HRID 600638 reaction equation
[CH2:1]([O:8][C:9](=[O:14])[NH:10][CH2:11][CH2:12][OH:13])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(N(CC)C(C)C)(C)C>ClCCl.CS(C)=O>[CH2:1]([O:8][C:9](=[O:14])[NH:10][CH2:11][CH:12]=[O:13])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 2

HCID 81531DiisopropylethylamineHCID 280458benzyl N-(2-hydroxyethyl)carbamate

Product 1

HCID 11217768benzyl N-(2-oxoethyl)carbamateYield 82.2%

Reagents, catalysts & solvents 2

HCID 679Dimethyl SulfoxideSolventHCID 6344DichloromethaneSolvent2×

Procedure

To a stirred solution of (2-hydroxyethyl)-carbamic acid benzyl ester (1.0 g, 5.1 mmol) and N,N-diisopropylethylamine (1.78 mL, 10.2 mmol) in dichloromethane (15 mL) was added a solution of sulfur trioxide-pyridine complex (1.63 g, 10.2 mmol) in dimethyl sulfoxide (15 mL) at −20° C. After 1 h, the reaction was warmed to room temperature, diluted with dichloromethane (50 mL) and washed with 1.0 N HCl (50 mL) and brine. The organics were separated, dried with anhydrous sodium sulfate, filtered, and concentrated. The crude material was purified by silica gel chromatography, eluting with ethyl acetate in hexanes (0% to 80% gradient) to give the title product (810 mg, 82%). 1H NMR (CDCl3, 300 MHz) δ (ppm): 9.5 (s, 1H) 7.4-7.2 (m, 5H), 5.1 (s, 2H), 3.9 (d, J=5.8 Hz, 2H), 2.9-3.3 (br, 1H).

Workup

  1. washwashed with 1.0 N HCl (50 mL) and brine
  2. customThe organics were separated
  3. dry with materialdried with anhydrous sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customThe crude material was purified by silica gel chromatography
  7. washeluting with ethyl acetate in hexanes (0% to 80% gradient)

Sources & evidence

ORD record
ord-fb9db6c25c5b412abf6fef28f1e6c989
Source dataset
uspto-grants-2011_03
Patent number
US07902221B2

Linked notes

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