Sodium Chloride → t-Butyl 5-methylpyrazine-2-carboxylate

HRID 2281839Notes

Reaction equation

HRID 2281839 reaction equation
[CH3:1][C:2]1[CH:7]=[N:6][C:5]([C:8]([OH:10])=[O:9])=[CH:4][N:3]=1.ClC(Cl)(Cl)C(=N)O[C:15]([CH3:18])([CH3:17])[CH3:16].[Na+].[Cl-].CCOC(C)=O>C1COCC1>[CH3:1][C:2]1[N:3]=[CH:4][C:5]([C:8]([O:10][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:9])=[N:6][CH:7]=1

Participants

6

Reactant 4

HCID 5234Sodium ChlorideHCID 8857Ethyl AcetateHCID 1228315-Methyl-2-pyrazinecarboxylic acidHCID 2734700Tert-butyl 2,2,2-trichloroethanimidate

Product 1

HCID 57475683t-Butyl 5-methylpyrazine-2-carboxylateYield 99.6%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A boron trifluoride-diethyl ether complex (91.7 μL) was added dropwise to a suspension of 2-methylpyrazine-5-carboxylic acid (1 g) and tert-butyl 2,2,2-trichloroacetimidate (4.75 g) in THF (20 mL) under ice-cooling. The reaction solution was warmed to RT, followed by stirring for 2 h. A saturated NaCl solution and EtOAc were added to the reaction solution, and the organic layer was separated. The organic layer was dried over anhydrous MgSO4, and the insoluble matter was separated by filtration. The filtrate was concentrated and purified by silica gel column chromatography to obtain the title compound (1.4 g). 1H-NMR (CDCl3) δ (ppm): 1.65 (s, 9H), 2.65 (s, 3H), 8.57 (d, J=1.2 Hz, 1H), 9.10 (d, J=1.6 Hz, 1H).

Workup

  1. temperaturecooling
  2. customthe organic layer was separated
  3. dry with materialThe organic layer was dried over anhydrous MgSO4
  4. customthe insoluble matter was separated by filtration
  5. concentrationThe filtrate was concentrated
  6. custompurified by silica gel column chromatography

Sources & evidence

ORD record
ord-a2a3b8cf8d7d48a2bf4123d4339479c0
Source dataset
uspto-grants-2015_09
Patent number
US09139594B2

Reaction notes

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