Benzylamine → 4-(1-Benzylamino-ethylidene)-pent-2-enedioic acid dimethyl ester

HRID 919652Notes

Reaction equation

HRID 919652 reaction equation
[CH2:1]([NH2:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:9][O:10][C:11](=[O:16])[CH2:12][C:13](=O)[CH3:14].[CH3:17][O:18][C:19](=[O:22])[C:20]#[CH:21]>CO>[CH3:17][O:18][C:19](=[O:22])[CH:20]=[CH:21][C:12](=[C:13]([NH:8][CH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1)[CH3:14])[C:11]([O:10][CH3:9])=[O:16]

Participants

5

Reactant 3

HCID 7504BenzylamineHCID 7757Methyl acetoacetateHCID 13536Methyl propiolate

Product 1

HCID 728337734-(1-Benzylamino-ethylidene)-pent-2-enedioic acid dimethyl esterYield 68.4%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

Benzyl amine (2.0 mL, 18.7 mmol) was dissolved in MeOH (60 mL). 3-Oxo-butyric acid methyl ester (2.4 mL, 22.4 mmol) was added and the mixture was refluxed for 2 h. The mixture was cooled slightly, and propynoic acid methyl ester (2.5 mL, 28 mmol) was added. The mixture was then refluxed for 48 h. The solvent was evaporated, and the residual oil was recrystallized with MeOH to give 3.7 g of the title compound as a pale yellow solid. 1H NMR (CDCl3, 200 MHz): 8=10.94 (br s, 1H), 7.75 (d, 1H, J=15.4 Hz), 7.20-7.45 (m, 5H), 6.09 (d, 1H, J=15.4 Hz), 4.58 (d, 1H, J=6.2 Hz), 3.78 (s, 3H), 3.74 (s, 3H), 2.27 (s, 3H).

Workup

  1. temperaturethe mixture was refluxed for 2 h
  2. temperatureThe mixture was cooled slightly
  3. temperatureThe mixture was then refluxed for 48 h
  4. customThe solvent was evaporated
  5. customthe residual oil was recrystallized with MeOH

Sources & evidence

ORD record
ord-82cb3a8ac6154409bee99774ee62af7d
Source dataset
uspto-grants-2016_03
Patent number
US09271970B2

Reaction notes

Loading…