4-Aminobenzonitrile → 4-[(2-Ethoxy-3,4-dioxocyclobut-1-en-1-yl)amino]benzonitrile

HRID 260795

Reaction equation

HRID 260795 reaction equation
[NH2:1][C:2]1[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[CH:4][CH:3]=1.[CH2:10]([O:12][C:13]1[C:14](=O)[C:15](=[O:20])[C:16]=1[O:17]CC)[CH3:11]>C(O)C>[O:17]=[C:16]1[C:15](=[O:20])[C:14]([NH:1][C:2]2[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[CH:4][CH:3]=2)=[C:13]1[O:12][CH2:10][CH3:11]

Participants

4

Reactant 2

HCID 133964-AminobenzonitrileHCID 123228Diethyl squarate

Product 1

HCID 108240584-[(2-Ethoxy-3,4-dioxocyclobut-1-en-1-yl)amino]benzonitrile

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

4-Aminobenzonitrile (17.58 g, 149 mmol) was added to a solution of 3,4-diethoxy-3-cyclobutene-1,2-dione (25.31 g, 149 mmol) in absolute ethanol (450 mL). The mixture was heated at reflux overnight and the resulting suspension filtered hot to remove a small amount of a dirty yellow solid (discarded). The tiltrate was gradually concentrated to afford several crops of 4-(3,4-dioxo-2-ethoxy-cyclobut-1-enylamino)-benzonitrile, as a bright yellow solid, which were collected by filtration and combined. Yield: 29.11 g (81%): 1H NMR (DMSO-d6): δ 11.07 (s, 1H), 7.81 (d, 2H), 7.56 (d, 2H), 4.79 (q, 2H), 1.46 (t, 3H).

Workup

  1. temperatureThe mixture was heated
  2. temperatureat reflux overnight
  3. filtrationthe resulting suspension filtered hot
  4. customto remove a small amount of a dirty yellow solid (discarded)
  5. concentrationThe tiltrate was gradually concentrated

Sources & evidence

ORD record
ord-df06eb08e0e64101b8733fed77b72d36
Source dataset
uspto-grants-1996_06
Patent number
US05530025

Linked notes

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