168418-67-5

Upstream product

• 501-53-1 benzyl chloroformate 
• 1007122-78-2 6-amino-non-1-ene 
• 503560-92-7 (6S,1'R)-(-)-N-(1-phenylbutoxy)-6-non-1-enylamine 
• 34164-50-6 4-penten-1-ylmagnesium bromide 
• 7103-09-5 4-but-1-enylmagnesium bromide 

Downstream Products

• 155511-85-6 (2S,5S)-(+)-1-(benzyloxycarbonyl)-5-hydroxy-2-propylpyperidine 
• 140-55-6 (3S,6S)-6-propylpiperidin-3-ol 
• 185758-26-3 (S)-2-Propyl-3,4-dihydro-2H-pyridine-1-carboxylic acid benzyl ester 
• 168418-66-4 (2S,6S)-N-benzyloxycarbonyl-6-propyl-2-hydroxymethyl-piperidine 

Relevant 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

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.

ASYMMETRIC SYNTHESIS OF OF INDOLIZIDINES 167B AND 223AB

The total synthesis of (+)-indolizidine 167B (1) and the formal synthesis (-)-indolizidine 223AB (2) starting with l- and d-norvaline-derived cis-hydroxymethyl-6-propylpiperidines (3 and ent-3), respectively, are described.