Allyl bromide → HCID 19017714, compound

HRID 1728343Notes

Reaction equation

HRID 1728343 reaction equation
[NH2:1][C:2]1[C:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])=[CH:5][N:4]([CH3:12])[N:3]=1.C[Si](C)(C)[N-][Si](C)(C)C.[Na+].O1C[CH2:26][CH2:25][CH2:24]1.C(Br)C=C>CN1CCCN(C)C1=O.O>[CH2:26]([NH:1][C:2]1[C:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])=[CH:5][N:4]([CH3:12])[N:3]=1)[CH:25]=[CH2:24]

Participants

7

Reactant 4

HCID 7841Allyl bromideHCID 8028TetrahydrofuranHCID 252927ethyl 3-amino-1-methyl-1H-pyrazole-4-carboxylateHCID 2724254Sodium bis(trimethylsilyl)amide

Product 1

HCID 19017714HCID 19017714, compoundYield 34%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 816462(1H)-Pyrimidinone, tetrahydro-1,3-dimethyl-Solvent

Conditions

Temperature
-40 °C

Procedure

Ethyl 3-amino-1-methylpyrazole-4-carboxylate, prepared by the method of Schmidt et al., Helvetica Chim. Acta. 42 349 (1959), (12.5 g, 7.40 mmol) was dissolved in 80 mL of 1,3-dimethyl-3,4,5,6-tetrahydro2(1H)-pyrimidinone (DMPU) and cooled to -40° C. A 1M solution of sodium hexamethyldisilazide in tetrahydrofuran (80 mL, 8.0 mmol) was added dropwise. After 8 minutes at -35° C., the reaction was cooled to -40° C. and 13.16 g (10.8 mmol) of allyl bromide was added dropwise. The reaction mixture was allowed to warm to 10° C. over 90 minutes. Water was added and the mixture was extracted with ether. The combined organic extracts were washed with water (3×), dried over sodium sulfate and concentrated in vacuo to afford a mixture of mono- and di-allyl products plus 10% unreacted starting material. Separation by column chromatography on silica gel eluting with 30% ethyl acetate in hexane afforded 5.26 g (34%) of the title compound as a colorless oil.

Workup

  1. temperaturethe reaction was cooled to -40° C.
  2. temperatureto warm to 10° C. over 90 minutes
  3. extractionthe mixture was extracted with ether
  4. washThe combined organic extracts were washed with water (3×)
  5. dry with materialdried over sodium sulfate
  6. concentrationconcentrated in vacuo
  7. customto afford
  8. customSeparation by column chromatography on silica gel eluting with 30% ethyl acetate in hexane

Sources & evidence

ORD record
ord-4ba102f6688a42fbb4e04fcc9da9c98a
Source dataset
uspto-grants-1994_07
Patent number
US05326776

Reaction notes

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