71226-60-3

Upstream product

• 143211-19-2 (E)-1-hydroxy-10-methylundec-8-ene 
• 143211-16-9 (Z)-1-hydroxy-10-methylundec-8-ene 
• 143211-13-6 8-hydroxy-octanal cyclohemiacetal 
• 179617-46-0 2-((E)-8-Methyl-non-6-enyl)-malonic acid dimethyl ester 
• 179617-42-6 2-((E)-6-Methyl-hept-4-enyl)-malonic acid dimethyl ester 
• 179617-59-5 (E)-10-Methyl-undec-8-enoic acid methyl ester 
• 179617-47-1 trans-6-methyl-hept-4-enoic acid ethyl ester 
• 143211-20-5 (E)-10-Methylundec-8-enoic acid 
• 112375-54-9 methyl (E)-8-methyl-6-nonenoate 
• 90369-20-3 (E)-1-hydroxy-8-methylnon-6-ene 
• 179617-41-5 Methanesulfonic acid (E)-6-methyl-hept-4-enyl ester 
• 59721-82-3 (E)-1-hydroxy-6-methylhept-4-ene 

Relevant academic research and scientific papers

A general and stereoselective synthesis of the capsaicinoids via the orthoester Claisen rearrangement

Capsaicin, a main pungent principle of hot pepper, and its 15 analogs have been efficiently synthesized. The key step of this synthetic scheme is the orthoester Claisen rearrangement, which transformed allylic alcohols 2A-C to (E)-alkenoates 3A-C (E/Z > 100) in a highly stereoselective manner. The subsequent carbon chain elongations on 3 based on the cyanation or the malonic acid ester synthesis afforded (E)-alkenoic acids 8, which were converted to the corresponding acid chloride and then coupled with vanillylamine to give capsaicinoids. HPLC and CE (capillary electrophoresis) analyses of these capsaicinoids were also carried out.

An Alternate Synthesis of the Capsaicinoids

Five capsaicinoids, the pungent ingredients of hot peppers, have been efficiently synthesized by a method involving the Wittig reaction between isobutyl triphenylphosphorane and the appropriate lactols (3), followed by the nitrous acid-induced isomerization of the resultant (Z)-olefins (4) to (E)-olefins (5).