Diisopropylethylamine → 2-((Methoxy)(4-phenoxyphenyl)methylene)malononitrile

HRID 334181Notes

Reaction equation

HRID 334181 reaction equation
[C:1]([C:3]([C:19]#[N:20])=[C:4]([OH:18])[C:5]1[CH:10]=[CH:9][C:8]([O:11][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)=[CH:7][CH:6]=1)#[N:2].[CH:21](N(C(C)C)CC)(C)C.C[Si](C=[N+]=[N-])(C)C>C(#N)C.CO.C1COCC1>[C:1]([C:3]([C:19]#[N:20])=[C:4]([O:18][CH3:21])[C:5]1[CH:10]=[CH:9][C:8]([O:11][C:12]2[CH:13]=[CH:14][CH:15]=[CH:16][CH:17]=2)=[CH:7][CH:6]=1)#[N:2]

Participants

7

Conditions

Temperature
20 °C

Procedure

1,1-Dicyano-2-hydroxy-2-(4-phenoxyphenyl)ethene (56.5 g) in acetonitrile (780 mL) and methanol (85 mL) is stirred under nitrogen at 0° C. while adding diisopropylethylamine (52.5 mL) followed by 2M trimethylsilyldiazomethane (150 mL) in THF. The reaction is stirred for 2 days at 20° C., and then 2 g of silica is added (for chromatography). The brown-red solution is evaporated in vacuo, the residue dissolved in ethyl acetate and washed well with water then brine, dried and evaporated. The residue is extracted with diethyl ether (3×250 mL), decanting from insoluble oil. Evaporation of the ether extracts gives 22.5 g of 1,1-dicyano-2-methoxy-2-(4-phenoxyphenyl)ethene as a pale orange solid. The insoluble oil is purified by flash chromatography to give 15.0 g of a red-orange oil. 1,1-Dicyano-2-methoxy-2-(4-phenoxyphenyl)ethene (22.5 g) and 1,1-dicyano-2-methoxy-2-(4-phenoxyphenyl)ethene oil (15 g) are treated with a solution of hydrazine hydrate (18 mL) in ethanol (25 mL) and heated on the steambath for 1 hour. Ethanol (15 mL) is added followed by water (10 mL). The precipitated solid is collected and washed with ethanol:water (4:1) and then dried in air to give 3-amino-4-cyano-5-(4-phenoxyphenyl)pyrazole as a pale orange solid.

Workup

  1. addition2 g of silica is added (for chromatography)
  2. customThe brown-red solution is evaporated in vacuo
  3. dissolutionthe residue dissolved in ethyl acetate
  4. washwashed well with water
  5. dry with materialbrine, dried
  6. customevaporated
  7. extractionThe residue is extracted with diethyl ether (3×250 mL)
  8. customdecanting from insoluble oil
  9. customEvaporation of the ether

Sources & evidence

ORD record
ord-c58e98a928f64c48b3f817e08e5d0d3c
Source dataset
uspto-grants-2014_11
Patent number
US08883803B2

Reaction notes

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