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

HRID 921982Notes

Reaction equation

HRID 921982 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

Reactant 3

HCID 81531DiisopropylethylamineHCID 167693TrimethylsilyldiazomethaneHCID 223471552-(Hydroxy-(4-phenoxyphenyl)methylene)propanedinitrile

Product 1

HCID 223472272-((Methoxy)(4-phenoxyphenyl)methylene)malononitrile

Reagents, catalysts & solvents 3

HCID 887MethanolSolventHCID 6342AcetonitrileSolventHCID 8028TetrahydrofuranSolvent

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-a0a8daae1df847e48085d468a504cd24
Source dataset
uspto-grants-2016_03
Patent number
US09278100B2

Reaction notes

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