Potassium Cyanide → HCID 23297209, compound
Reaction equation
[NH2:1][C@:2]([CH2:6][C:7]1[CH:12]=[CH:11][C:10]([Cl:13])=[C:9]([Cl:14])[CH:8]=1)([CH3:5])[CH2:3][OH:4].ClC1C=C(C[C:24](=[O:26])C)C=CC=1Cl.[C-]#[N:28].[K+].C(=O)([O-])[O-].[NH4+].[NH4+]>>[Cl:14][C:9]1[CH:8]=[C:7]([CH:12]=[CH:11][C:10]=1[Cl:13])[CH2:6][C:2]1([CH3:5])[NH:1][C:24](=[O:26])[NH:28][C:3]1=[O:4]Participants
Procedure
Advantageously, compared to this preparation which comprises six steps in all, the preferred process for the purposes of the invention, which is faster and more economical, enables (S)-(-)-2-amino-2-(3,4-dichlorobenzyl)-1-propanol to be prepared in four synthesis steps from 3,4-dichlorophenylacetone. Essentially, the process consists in reacting the ketone by the Bucherer-Berg reaction with potassium cyanide and ammonium carbonate to obtain (+/-)-5-(3,4-dichlorobenzyl)-5-methylhydantoin, which is subjected in an alkaline aqueous-acetone medium to a stereospecific salification with (R)-(+)-α-methylbenzylamine so as to obtain the addition salt thereof with the (S)-(-) enantiomer of the hydantoin, which, being insoluble, is filtered off, and from which (S)-(-)-5-(3,4-dichlorobenzyl)-5-methylhydantoin is obtained in a state of optical purity greater than 98% by treatment in an acid solution.
Workup
- customAdvantageously, compared to this preparation which
Sources & evidence
- ORD record
- ord-329d67dacbec4948bc6b6908d3b435ed
- Source dataset
- uspto-grants-1994_09
- Patent number
- US05348980
Reaction notes
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