Ethyl bromoacetate → tert-Butyl (3R)-6-cyclohexyl-3-{3-[(2-ethoxy-2-oxoethoxy)methyl]-1,2,4-oxadiazol-5-yl}hexanoate

HRID 2183046Notes

Reaction equation

HRID 2183046 reaction equation
[H-].[Na+].[CH:3]1([CH2:9][CH2:10][CH2:11][C@@H:12]([C:21]2[O:25][N:24]=[C:23]([CH2:26][OH:27])[N:22]=2)[CH2:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:8][CH2:7][CH2:6][CH2:5][CH2:4]1.Br[CH2:29][C:30]([O:32][CH2:33][CH3:34])=[O:31]>O1CCCC1.C(OCC)(=O)C>[CH:3]1([CH2:9][CH2:10][CH2:11][C@@H:12]([C:21]2[O:25][N:24]=[C:23]([CH2:26][O:27][CH2:29][C:30]([O:32][CH2:33][CH3:34])=[O:31])[N:22]=2)[CH2:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:4][CH2:5][CH2:6][CH2:7][CH2:8]1

Participants

6

Reactant 3

HCID 7748Ethyl bromoacetateHCID 24758Sodium hydrideHCID 59909744tert-Butyl(3R)-6-cyclohexyl-3-[3-(hydroxymethyl)-1,2,4-oxadiazol-5-yl]hexanoate

Product 1

HCID 59909756tert-Butyl (3R)-6-cyclohexyl-3-{3-[(2-ethoxy-2-oxoethoxy)methyl]-1,2,4-oxadiazol-5-yl}hexanoateYield 63.8%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent2×HCID 8857Ethyl AcetateSolvent

Conditions

Temperature
0 °C

Procedure

A suspension of sodium hydride 60% suspension in mineral oil (13 mg, 0.33 mmol) in anhydrous tetrahydrofuran (1 ml) was cooled to 0° C. and treated with a solution of tert-butyl (3R)-6-cyclohexyl-3-[3-(hydroxymethyl)-1,2,4-oxadiazol-5-yl]hexanoate (Preparation 85) (105 mg, 0.30 mmol) in anhydrous tetrahydrofuran (1 ml) and stirred under a nitrogen atmosphere for 1 hour. Ethyl bromoacetate (37 μl, 0.33 mmol) was added and the mixture was stirred for 18 hours, being allowed to warm to room temperature over this time. The reaction mixture was diluted with ethyl acetate and washed with water and brine, dried over anhydrous sodium sulphate, filtered and the solvent removed under reduced pressure. The solid was purified by column chromatography on silica gel eluting with a gradient system of pentane:ethyl acetate (99:1) to pentane:ethyl acetate (80:20) to afford the title compound as a colourless oil (84 mg).

Workup

  1. stirringthe mixture was stirred for 18 hours
  2. temperatureto warm to room temperature over this time
  3. washwashed with water and brine
  4. dry with materialdried over anhydrous sodium sulphate
  5. filtrationfiltered
  6. customthe solvent removed under reduced pressure
  7. customThe solid was purified by column chromatography on silica gel eluting with a gradient system of pentane:ethyl acetate (99:1) to pentane:ethyl acetate (80:20)

Sources & evidence

ORD record
ord-4457180940e1419eafe1a53be4818338
Source dataset
uspto-grants-2005_05
Patent number
US06897306B2

Reaction notes

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