Pyridine → HCID 21525327, compound

HRID 1658692Notes

Reaction equation

HRID 1658692 reaction equation
Cl.[CH2:2]([NH:4][CH2:5][NH:6][C:7](=[O:14])[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[CH3:3].[OH-].[Na+].[C:17](Cl)(Cl)=[O:18].N1C=CC=CC=1>O.O1CCCC1>[C:8]1([C:7]2[O:14][C:17](=[O:18])[N:4]([CH2:2][CH3:3])[CH2:5][N:6]=2)[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1

Participants

7

Reactant 4

HCID 1049PyridineHCID 6371PhosgeneHCID 14798Sodium HydroxideHCID 2152534152387-57-2

Product 1

HCID 21525327HCID 21525327, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

A suspension of 21.5 g of N-(ethylaminomethyl)-benzamide hydrochloride (0.1 mole) in 300 ml of water is neutralised at 0°-25°C with 50 ml of 2 normal sodium hydroxide solution (0.1 mole). Extraction is performed with ethyl acetate, the organic phase is dried over magnesium sulphate and the solvent is evaporated off. The residue is taken up in 150 ml of tetrahydrofuran and the solution is treated dropwise with 9.9 g of phosgene (0.1 mole) in 150 ml of tetrahydrofuran. The addition is effected at 0°-25°C over the course of 1 hour. Then a solution of 15.8 g (0.2 mole) of pyridine in 150 ml of tetrahydrofuran is added over the course of a further hour. Stirring of the reaction mixture is continued for 2 hours and it is then refluxed for 3 hours. After the reaction mixture has cooled, the precipitate which has formed is filtered off and the filtrate is evaporated to dryness. The residue is taken up in chloroform and washed first with sodium bicarbonate solution and then with water. The solvent is evaporated off and crystallisation of the residue from ethyl acetate/n-hexane yields 6-phenyl-3-ethyl-3,4-dihydro-2H-1,3,5-oxadiazin-2-one with a melting point of 96°-98°C (compound 1).

Workup

  1. extractionExtraction
  2. dry with materialthe organic phase is dried over magnesium sulphate
  3. customthe solvent is evaporated off
  4. additionThe addition
  5. customis effected at 0°-25°C over the course of 1 hour
  6. temperatureit is then refluxed for 3 hours
  7. temperatureAfter the reaction mixture has cooled
  8. customthe precipitate which has formed
  9. filtrationis filtered off
  10. customthe filtrate is evaporated to dryness
  11. washwashed first with sodium bicarbonate solution
  12. customThe solvent is evaporated off
  13. customcrystallisation of the residue from ethyl acetate/n-hexane

Sources & evidence

ORD record
ord-e754ac07eff34f44b764a4ef0104c695
Source dataset
uspto-grants-1976_06
Patent number
US03966721

Reaction notes

Loading…