Chloro-N,N-dimethylformiminium chloride → HCID 71743490, compound

HRID 880906Notes

Reaction equation

HRID 880906 reaction equation
[C:1]([NH:5]/[N:6]=[C:7](\[CH3:13])/[C:8]([O:10][CH2:11][CH3:12])=[O:9])([CH3:4])([CH3:3])[CH3:2].[Cl-].Cl[CH:16]=[N+](C)C.[C:20](=[O:23])(O)[O-].[Na+]>C1(C)C=CC=CC=1>[C:1]([N:5]1[CH:16]=[C:13]([CH:20]=[O:23])[C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[N:6]1)([CH3:4])([CH3:3])[CH3:2]

Participants

5

Reactant 3

HCID 77311Chloro-N,N-dimethylformiminium chlorideHCID 516892Sodium BicarbonateHCID 13675760HCID 13675760, compound

Product 1

HCID 71743490HCID 71743490, compound

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent2×

Procedure

To a yellow orange solution of (E)-ethyl 2-(2-tert-butylhydrazono)propanoate (22.9 g, 123 mmol) in toluene (300 mL) was added (chloromethylene)dimethylammonium chloride (Vilsmeier salt, 34.0 g, 252 mmol) in a single portion. The suspension was stirred 3 hours at room temperature, slowly becoming a biphasic mixture of toluene over a thick orange oil. The reaction mixture was cooled to 0° C. and slowly neutralized with saturated aqueous sodium bicarbonate. The layers were separated and the aqueous layer extracted with additional ethyl acetate (2×200 mL). The organic layers were combined, washed with 200 mL brine, dried over sodium sulfate, filtered and concentrated to yield ethyl 1-tert-butyl-4-formyl-1H-pyrazole-3-carboxylate (18.6 g) as a tan-orange oil which solidified on standing. +APCI (M+H) 225.1; 1H NMR (400 MHz, CDCl3, δ): 10.37 (s, 1H), 8.14 (s, 1H), 4.48 (q, J=7.0 Hz, 2H), 1.65 (s, 9H), 1.44 (t, 3H).

Workup

  1. customThe layers were separated
  2. extractionthe aqueous layer extracted with additional ethyl acetate (2×200 mL)
  3. washwashed with 200 mL brine
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-755b871922374db2aa113bc70ababdd9
Source dataset
uspto-grants-2015_03
Patent number
US08993586B2

Reaction notes

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