Citric Acid → HCID 21266052, compound

HRID 566316Notes

Reaction equation

HRID 566316 reaction equation
[NH:1]([CH:3]([CH2:5][CH2:6][CH2:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[CH3:4])[NH2:2].C(N(CC)CC)C.[CH3:21][O:22][C:23](OC)=[C:24]([C:27]#[N:28])[C:25]#[N:26].C(O)(=O)CC(CC(O)=O)(C(O)=O)O>CO.O>[NH2:28][C:27]1[N:1]([CH:3]([CH2:5][CH2:6][CH2:7][C:8]2[CH:9]=[CH:10][CH:11]=[CH:12][CH:13]=2)[CH3:4])[N:2]=[C:23]([O:22][CH3:21])[C:24]=1[C:25]#[N:26]

Participants

7

Reactant 4

HCID 311Citric AcidHCID 8471TriethylamineHCID 1100797064672-72-6HCID 12874625HCID 12874625, compound

Product 1

HCID 21266052HCID 21266052, compoundYield 80.9%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Conditions

Temperature
20 °C

Procedure

3.6 g of 2-hydrazino-5-phenylpentane are dissolved in 40 ml of methanol, and 2.8 ml of triethylamine are added. Then, 2.8 g of 1,1-dimethoxy-2,2-dicyanoethylene are added at approx. 0° C. The reaction solution is warmed to approx. 20° C. and stirred for 1.5 hours at approx. 20° C. For work-up, the mixture is diluted with water, acidified with citric acid and extracted twice with dichloromethane. The combined dichloromethane phases are dried with magnesium sulphate and evaporated in vacuo. This gives 5.1 g of a yellow oil, which crystallizes slowly. The oil is chromatographed on silica gel (Merck Si 60 0.04-0.063 mm) with a petroleum ether/ethyl acetate mixture in a ratio of 5:1 to 1:1. This gives a fraction which, after evaporation in vacuo, affords 4.6 g (=80.9% of theory) of 5-amino-4-cyano-3-methoxy-1-[(5-phenyl)-pent-2-yl]-pyrazole.

Workup

  1. extractionextracted twice with dichloromethane
  2. dry with materialThe combined dichloromethane phases are dried with magnesium sulphate
  3. customevaporated in vacuo
  4. customThis gives 5.1 g of a yellow oil, which crystallizes slowly
  5. customThe oil is chromatographed on silica gel (Merck Si 60 0.04-0.063 mm) with a petroleum ether/ethyl acetate mixture in a ratio of 5:1 to 1:1
  6. customThis gives a fraction which
  7. customafter evaporation in vacuo

Sources & evidence

ORD record
ord-bbcced926d7b49a4a1ad03814ee79b9d
Source dataset
uspto-grants-2001_01
Patent number
US06174884B1

Reaction notes

Loading…