157982-67-7

Upstream product

• 157982-65-5 tert-butyl N-(benzyloxycarbonyl)-2-(methoxycarbonylethyl)-pipecolate 
• 157982-64-4 tert-butyl N-(benzyloxycarbonyl)-2-(carboxyethyl)-pipecolate 
• 157982-63-3 tert-butyl N-(benzyloxycarbonyl)-2-(3-hydroxy-propyl)-pipecolate 
• 129605-87-4 tert-Butyl N-(benzyloxycarbonyl)-2(RS)-allylpipecolate 
• 157982-66-6 N-(benzyloxycarbonyl)-2-(methoxycarbonylethyl)-pipecolic acid 

Downstream Products

• 13618-93-4 indolizidine 
• 157982-69-9 3-(1'-benzyloxycarbonyl-1',4',5',6'-tetrahydropyridin-2'-yl)-propanamide 
• 157982-73-5 6-benzyloxycarbonyl-1-oxa-6-azaspiro[4.5]decan-2-one 
• 157982-74-6 6-benzyloxycarbonyl-1,6-diazaspiro[4.5]decane-2-one 
• 157982-70-2 C₂₂H₃₆N₂O₃Si₂ 
• 215106-50-6 6-benzyloxycarbonyl-10-iodo-1-oxa-6-azaspiro[4.5]decan-2-one 
• 157982-72-4 10-Iodo-2-oxo-1,6-diaza-spiro[4.5]decane-6-carboxylic acid benzyl ester 
• 157982-71-3 10-Iodo-2-oxo-1-oxa-6-aza-spiro[4.5]decane-6-carboxylic acid benzyl ester 
• 157982-68-8 6-(2-Carboxy-ethyl)-3,4-dihydro-2H-pyridine-1-carboxylic acid benzyl ester 
• 2740-00-3 indolizidin-3-one 

Relevant academic research and scientific papers

Decarbonylation of α-tertiary amino acids application to the synthesis of polyhydroxylated indolizidines from D,L-pipecolic acid

The decarbonylation of the bicyclic α-tertiary carboxamido acid 11 led to the enamide 12, easily transformed into the indolizidine alkaloid 8,8a- trans-8-hydroxy-indolizidine 14. Likewise, the same process applied to the α-substituted pipecolic acid derivative 5 led to the unsaturated ester 6 which was easily transformed either into δ-coniceine 9 or to 14. The thermal fragmentation of the acyl derivative 22 led to the enamide 24 which has been transformed into (±)-swainsonine 26.

Synthesis of azaspiro[4.5]decane systems by oxidative cyclization of olefinic precursors

The synthesis of 6-benzyloxycarbonyl-1-oxa-6-azaspiro[4.5]decan-2-one (17) and 6-benzyloxycarbonyl-1,6-diazaspiro[4.5]decan-2-one (18) from the D,L-pipecolic acid derivative 10, is described. The synthesis of (±)-6- benzyl-3-methyl-1,6-diazaspiro[4.5]dec-3-ene-2,7-dione (29), the spiro structural unit of (±)-pandamarine (8) has been achieved by oxidative cyclization of the (Z) and (E) isomers of 5-(N-benzyl-4- carboxamidobutylidene)-3-methyl-3-pyrrolin-2-one (25) and (26). The stereoselectivity obtained in the intramolecular cyclization process has also been discussed.

DPPA-promoted decarbonylation of a N-Cbz-(D,L)-pipecolinic acid derivative: An easy entry to [4.5]spirolactams and [4.5]spirolactones. Total synthesis of (±)-δ-coniceine

The synthesis of 6-benzyloxycarbonyl-1-oxa-6-azaspiro[4.5]decane 2-one 7a and 6-benzyloxycarbonyl-1,6-diazaspiro[4.5]decane-2-one 7b from (D,L)-pipecolinic acid is described. The extremely clean decarboxylation of the α-substituted amino acid 9d promoted by diphenylphosphorazidate (DDPA) is the key step of our strategy. The total synthesis of (±)-δ-coniceine (16) from the enamine ester 10a has been succesfully achieved.