Acetic Acid → Methyl 2-cyano-4-methylpent-2-enoate

HRID 479073Notes

Reaction equation

HRID 479073 reaction equation
[CH:1](=O)[CH:2]([CH3:4])[CH3:3].[CH3:6][O:7][C:8](=[O:12])[CH2:9][C:10]#[N:11].[OH-].[NH4+].C(O)(=O)C>C1(C)C=CC=CC=1>[CH3:6][O:7][C:8](=[O:12])[C:9]([C:10]#[N:11])=[CH:1][CH:2]([CH3:4])[CH3:3]

Participants

6

Reactant 4

HCID 176Acetic AcidHCID 6561IsobutyraldehydeHCID 7747Methyl cyanoacetateHCID 14923Ammonium Hydroxide

Product 1

HCID 53793275Methyl 2-cyano-4-methylpent-2-enoateYield 90.4%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A solution of isobutyraldehyde (30.0 g, 416 mmol), methyl-cyano-acetate (20.6 g, 208 mmol), ammonium hydroxide (3.2 g, 41.6 mmol) and acetic acid (5.0 g, 83.2 mmol) in 500 mL of toluene is warmed to reflux under a Dean-Stark trap for 12 hours. The mixture is cooled to room temperature and extracted with saturated NaHSO3 (3×100 mL), saturated NaHCO3 (3×100 mL), and 100 mL of brine. The organic layer is dried over Na2SO4, and the solvent is evaporated. The remaining oil is distilled under high vacuum (0.5 mm Hg, B.P.=115-120° C.) to give 28.8 g of 2-cyano-4-methyl-2-pentenoic acid methyl ester 61 as an oil (90% yield).

Workup

  1. temperatureto reflux under a Dean-Stark trap for 12 hours
  2. extractionextracted with saturated NaHSO3 (3×100 mL), saturated NaHCO3 (3×100 mL), and 100 mL of brine
  3. dry with materialThe organic layer is dried over Na2SO4
  4. customthe solvent is evaporated
  5. distillationThe remaining oil is distilled under high vacuum (0.5 mm Hg, B.P.=115-120° C.)

Sources & evidence

ORD record
ord-f638ec3f5c5945ee99aa797133237a23
Source dataset
uspto-grants-2003_11
Patent number
US06642398B2

Reaction notes

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