Birch reduction of (-)-ephedrine. Formation of a new, versatile intermediate for organic synthesis.
The reduction of (-)-ephedrine by lithium in liquid ammonia resulted in the formation of S-1-(1,4-cyclohexadien-1-yl)-N-methyl-2-propanamine. In addition to the reduction of the aromatic ring, the hydroxy group was reduced as well. The resulting 1,4-cyclohexadienyl group is a potentially versatile intermediate for further synthetic transformations. The ozonolysis of this group was investigated, producing derivatives of beta-keto-delta-methylamino esters and beta-keto aldehydes which could be subsequently converted to heterocycles. The restriction to rotation of the C-N bond in N-benzoyl-1-(1,4-cyclohexadien-1-yl)-N-methyl-2-propanamine is described.
Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel. gury@vms.huji.ac.il
Gury
G
Zvilichovsky
Isra
I
Gbara-Haj-Yahia
D002384:Catalysis; D004809:Ephedrine / Q000737:chemistry*; D004952:Esters / Q000138:chemical synthesis; D008094:Lithium / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry; D011437:Propylamines / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
D004952:Esters; D011437:Propylamines; D010126:Ozone; D008094:Lithium; D004809:Ephedrine