Eine einfache Synthese der enantiomeren (E)-9-Hydroxy-2-decensäuren

✍ Scribed by Schweitzer, Stefan ;Voß, Gundula ;Gerlach, Hans

• Book ID: 102366342
• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 474 KB
• Volume: 1994
• Category: Article
• ISSN: 0947-3440
• DOI: 10.1002/jlac.199419940213

✦ Synopsis

Simple Synthesis of the Enantiomeric (E)‐9‐Hydroxy‐2‐decenoic Acids

The enantiomeric (E)‐9‐Hydroxy‐2‐decenoic acids (1), components of the swarm settling pheromone in Apis mellifica L. (honey bee) have been synthesized. The lithium derivative of 1‐hexyne was treated with (R)‐(+)‐methyloxirane (2), (S)‐(−)‐2 or (±)‐2 to give the alkynols (R)‐(−)‐3, (S)‐(+)‐3 or (±)‐3, which could be isomerized with the sodium salt of 1,3‐propanediamine to give (R)‐(−)‐8‐nonyn‐2‐ol (4) and (±)‐4. These were methoxycarbonylated to produce the esters (R)‐(−)‐5, (S)‐(+)‐5 or (±)‐5. Selective hydrogenation in pyridine with Pd/BaSO~4~ as catalyst gave the (Z)‐esters (R)‐(−)‐6, (S)‐(+)‐6 or (±)‐6 which could be isomerized with photochemically generated phenylthio radicals to produce the (E)‐esters (R)‐(–)‐7, (S)‐(+)‐7 or (±)‐7. The acids present in the pheromone (R)‐(−)‐1, (S)‐(+)‐1 and (±)‐1 could be obtained by basic hydrolysis of the esters. The minor but important component 8 of the swarm settling pheromone has been synthesized by treating the Grignard reagent obtained from 5‐bromo‐guaiacol benzyl ether with ethylene oxide to give 9 in high yield. Hydrogenolytic removal of the benzyl group in 9 produced 8 directly. magnified image