Di-tert-butyl malonate → HCID 70978401, compound

HRID 1485405Notes

Reaction equation

HRID 1485405 reaction equation
CC([O-])(C)C.[K+].[C:7]([O:17][C:18]([CH3:21])([CH3:20])[CH3:19])(=[O:16])[CH2:8][C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10].Br[CH:23]([CH2:29]Br)[C:24]([O:26][CH2:27][CH3:28])=[O:25]>C1COCC1>[C:8]1([C:9]([O:11][C:12]([CH3:13])([CH3:14])[CH3:15])=[O:10])([C:7]([O:17][C:18]([CH3:21])([CH3:20])[CH3:19])=[O:16])[CH2:29][CH:23]1[C:24]([O:26][CH2:27][CH3:28])=[O:25]

Participants

5

Reactant 3

HCID 68324Di-tert-butyl malonateHCID 97945Ethyl 2,3-dibromopropionateHCID 23665647Potassium tert-butoxide2×

Product 1

HCID 70978401HCID 70978401, compoundYield 62%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a THF (200 mL) solution of t-BuOK (11.4 g, 102 mmol) at −30° C. was added slowly di-tert-butyl malonate (20 g, 92.6 mmol). The internal temperature was maintained between −30° C. and −10° C. After 30 min, ethyl 2,3-dibromopropanoate (29 g, 111.1 mmol) was added. The cooling bath was removed. After 1.5 h, the reaction mixture was cooled to −10° C. for addition of t-BuOK (11.4 g, 102 mmol). The cooling mixture was removed and the mixture was stirred overnight. The solution was evaporated and the residue was extracted with ethyl acetate (600 mL), dried and purified by CombiFlash (PE:EA=15:1) to afford 1,1-di-tert-butyl 2-ethyl cyclopropane-1,1,2-tricarboxylate (18 g, 62%). 1H NMR (300 MHz, CDCl3): δ 1.34-1.51 (t, J=7.2 Hz, 3H), 1.54-1.56 (d, J=4.4 Hz, 18H), 1.58-1.60 (m, 1H), 1.90-1.94 (m, 1H), 2.52-2.57 (m, 1H), 4.21-4.31 (m, 2H).

Workup

  1. temperatureThe internal temperature was maintained between −30° C. and −10° C
  2. customThe cooling bath was removed
  3. waitAfter 1.5 h
  4. customThe cooling mixture was removed
  5. customThe solution was evaporated
  6. extractionthe residue was extracted with ethyl acetate (600 mL)
  7. customdried
  8. custompurified by CombiFlash (PE:EA=15:1)

Sources & evidence

ORD record
ord-30f89681f1d446f3b2240b4523015fe8
Source dataset
uspto-grants-2016_08
Patent number
US09422292B2

Reaction notes

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