Radical addition to oxime ethers for asymmetric synthesis of beta-amino acid derivatives.
The diastereoselective alkyl radical addition to chiral oxime ethers was studied with a view to preparing enantiomerically pure alpha,beta-dialkyl-beta-amino acid derivatives. The phase transfer-catalyzed alkylation of Oppolzer's camphorsultam derivative of oxime ether proceeded smoothly to give the alkylated N-(beta-oximino)acyl derivatives. In the presence of BF3.OEt2, radical addition to the oxime ethers proceeded using triethylborane as the radical initiator to give alpha,beta-dialkyl-beta-amino acid derivatives with excellent diastereoselectivity.
Miyabe
Hideto
H
Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
Fujii
Kayoko
K
Naito
Takeaki
T
D000478:Alkylation; D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry; D004987:Ethers / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D010091:Oximes / Q000737:chemistry*; D013237:Stereoisomerism
D000596:Amino Acids; D004987:Ethers; D005609:Free Radicals; D010091:Oximes