180675-07-4

Upstream product

• 180675-05-2 (S)-1-[(3aS,4S,6R,6aS)-6-((R)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl]-4-oxo-piperidine-2-carboxylic acid ethyl ester 
• 357154-19-9 (1'R,2S)-4-oxo-1-(1'-phenylethyl)-piperidine-2-carboxylic acid ethyl ester 
• 180675-03-0 (S)-5-[(3aS,4S,6R,6aS)-6-((R)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl]-4-oxa-5-aza-spiro[2.4]heptane-6-carboxylic acid ethyl ester 
• 357154-22-4 (1'R)-2-[1'-phenylethyl]-5-(2-hydroxyethyl)isoxazolidine-3-carboxylic acid ethyl ester 

Downstream Products

• 180854-44-8 (2S)-N-tert-butoxycarbonyl-4-oxopiperidine-2-carboxylic acid ethyl ester 
• 65060-18-6 (2S)-4-oxopipecolic acid 
• 180854-45-9 ethyl cis-4-hydroxy-N-t-butoxycarbonyl-2-piperidinecarboxylate 

Relevant academic research and scientific papers

Practical synthesis of both enantiomers of protected 4-oxopipecolic acid

A new synthesis of both enantiomers of protected 4-oxopipecolic acid was achieved in six steps via 1,3-dipolar cycloaddition of C-ethoxycarbonyl N-(1R)-phenylethylnitrone to but-3-en-1-ol.

A new synthesis of (2S)-4-oxopipecolic acid by thermal rearrangement of enantiopure spirocyclopropaneisoxazolidine

A novel synthesis of (2S)-4-oxo-pipecolic acid is reported. The synthetic route employs as a key step the diastereoselective cycloaddition of the N- glycosylnitrone 7 to methylenecyclopropane followed by thermal rearrangement of the spirocyclopropaneisoxazolidine 8a. Stereoselective reduction of the N- BOC methyl ester of 4-oxopipecolic acid by L-selectride gives the protected cis-4-hydroxy-pipecolic acid 14.