1-Pentanol → Cadralazine

HRID 1414871

Reaction equation

HRID 1414871 reaction equation
Cl[C:2]1[N:3]=[N:4][C:5]([N:8]([CH2:13][CH3:14])[CH2:9][CH:10]([OH:12])[CH3:11])=[CH:6][CH:7]=1.[C:15]([NH:20][NH2:21])([O:17][CH2:18][CH3:19])=[O:16].C(O)CCCC>>[C:15]([NH:20][NH:21][C:2]1[N:3]=[N:4][C:5]([N:8]([CH2:13][CH3:14])[CH2:9][CH:10]([OH:12])[CH3:11])=[CH:6][CH:7]=1)([O:17][CH2:18][CH3:19])=[O:16]

Participants

4

Reactant 3

HCID 62761-PentanolHCID 20064Hydrazinecarboxylic acid, ethyl esterHCID 12237596HCID 12237596, compound

Product 1

HCID 2515Cadralazine

Procedure

A mixture of 11 g 3-chloro-6-[N-(2-hydroxypropyl)ethylamino]pyridazine which can be be prepared as described in Example 4 of U.S. Pat. No. 3,769,278 and 11 g monocarbethoxyhydrazine in 55 ml n. pentylalcohol is warmed up to 140° C and kept at this temperature for 4 hours. After cooling the solution is extracted several times with water and then extracts collected together are extracted with ethyl ether. The aqueous phase is treated at room temperature with sodium bicarbonate until complete precipitation. The precipitate is collected, washed with water and dried under vacuum at room temperature on phosphorus pentaoxide to give with good yield 3-(2-carbethoxyhydrazino)-6-[N-(2-hydroxypropyl)ethylamino]-pyridazine melting at 160° -162° C.

Workup

  1. customcan be be prepared
  2. temperatureAfter cooling the solution
  3. extractionis extracted several times with water
  4. customextracts collected together
  5. extractionare extracted with ethyl ether
  6. additionThe aqueous phase is treated at room temperature with sodium bicarbonate until complete precipitation
  7. customThe precipitate is collected
  8. washwashed with water
  9. customdried under vacuum at room temperature on phosphorus pentaoxide
  10. customto give

Sources & evidence

ORD record
ord-87e260cf7a34491aa0d2ecd2a1086d68
Source dataset
uspto-grants-1977_01
Patent number
US04002753

Linked notes

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