503560-75-6Relevant academic research and scientific papers
Chiral oxime ethers in asymmetric synthesis. Part 5. Asymmetric synthesis of 2-substituted 5- to 8-membered nitrogen heterocycles by oxime addition-ring-closing metathesis
Hunt, James C. A.,Laurent, Pierre,Moody, Christopher J.
, p. 2378 - 2389 (2007/10/03)
Addition of organometallic reagents to chiral oxime ethers 1 derived from an unsaturated aldehyde, or addition of an alkene containing organometallic to chiral aldoxime ethers 2 results in highly stereoselective formation of the hydroxylamines 6. N-Allylation gives the dienes 7 which undergo ring-closing metathesis (RCM) reaction to give the 5-, 6-, and 7-membered nitrogen heterocycles 8. Likewise, the benzyl carbamates 9, also prepared by stereoselective addition to oxime ethers, were converted into dienes 10, which underwent RCM to give the 5- to 8-membered azacycles 11. The oxime addition-RCM protocol is thus a versatile method for the asymmetric synthesis of nitrogen heterocycles, further exemplified by the conversion of the unsaturated heterocycles into chiral piperidines, including the alkaloid (-)-coniine.
