A new approach for asymmetric synthesis of (R)-3-methylpyrrolidine alkaloids from (S)-malic acid.
Diastereoselective methylation of dimethyl (S)-malate 7, followed by two, three-step reductive de-hydroxylation procedures afforded dimethyl (R)-2-methylsuccinate 11 in 80.2% e.e. and 84.7% e.e., respectively. The latter compound was further transformed into the natural enantiomers of the ant venom alkaloids (R)-leptothoracine 1 and (R)-3-methyl-N-(2-phenylethyl)-pyrrolidine 2.
Zheng
Xiao
X
Department of Chemistry, Xiamen University, PR China.
Huang
Pei-Qiang
PQ
Ruan
Yuan-Ping
YP
Lee
Albert W M
AW
Chan
Wing Hong
WH
D000470:Alkaloids / Q000138:chemical synthesis*; D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D008293:Malates / Q000737:chemistry*; D015394:Molecular Structure; D011759:Pyrrolidines / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000470:Alkaloids; D008293:Malates; D011759:Pyrrolidines; C030298:malic acid