Reaction equation
Cl.[CH:2](=[C:9]1[NH:13][C:12](=[O:14])[NH:11][C:10]1=[O:15])[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[C].[C].C[OH:19]>[Zn]>[C:12]([NH:13][C@H:9]([C:10]([OH:15])=[O:19])[CH2:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1)(=[O:14])[NH2:11]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Procedure
This Example shows the process in which hydrochloric acid is added first and then the zinc is added. A round bottom flask fitted with a stirrer, thermometer and condenser was charged with 10 grams of 5-benzalhydantoin (0.053 mole), 100 milliliters of methanol and then 21.0 grams of concentrated (37 weight percent) hydrochloric acid (0.213 mole of hydrogen chloride, 400 mole percent based on 5-benzalhydantoin) was added. To this was added very slowly with stirring 6.93 grams of zinc powder (0.106 mole, 200 mole percent based on 5-benzalhydantoin) over a period of 45 minutes. After 30 minutes of additional stirring, some of the zinc powder remained unreacted and so 5 grams more of concentrated hydrochloric acid was added. After about 60 minutes more of stirring, no unreacted zinc powder remained. The reaction was stirred an additional 2 hours. By UV analysis, the reaction mixture showed 98% reduction of the carbon-carbon double bond of the 5-benzalhydantoin. By workup of the reaction mixture N-carbamylphenylalanine was isolated. The melting point was determined to be 186°-188° C. corresponding to the literature melting point of 190° C., reported in Am. Chem. J. 45, 368 (1911) (compound referred to as 4-benzylhydantoic acid).
Workup
- additionis added first
- customA round bottom flask fitted with a stirrer
- additionwas added
- additionTo this was added very slowly
- stirringThe reaction was stirred an additional 2 hours
Sources & evidence
- ORD record
- ord-e9e57c45544a42c0b5db01e592d077f8
- Source dataset
- uspto-grants-1986_09
- Patent number
- US04613691
Linked notes
Loading…