157982-70-2

Upstream product

• 27607-77-8 trimethylsilyl trifluoromethanesulfonate 
• 157982-69-9 3-(1'-benzyloxycarbonyl-1',4',5',6'-tetrahydropyridin-2'-yl)-propanamide 
• 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 
• 157982-67-7 methyl 3-(1'-benzyloxycarbonyl-1',4',5',6'-tetrahydropyridine-2'-yl)-propanoate 
• 157982-68-8 6-(2-Carboxy-ethyl)-3,4-dihydro-2H-pyridine-1-carboxylic acid benzyl ester 

Downstream Products

• 157982-74-6 6-benzyloxycarbonyl-1,6-diazaspiro[4.5]decane-2-one 

Relevant academic research and scientific papers

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.