摘要:
Double deprotonation of either (E,E)-3-methyl-2,4-hexadienoic acid 2. or 4,6-dimethyldihydro-2-pyrone 3 generates apparently the same lithium trienediolate, which affords omega-hydroxy acids 9 on reaction with ketones 7. Hydroxy acids 9 arc easily dehydrated to octatrienoic acids 5. which are structurally related to retinoic acid. Similarly, sorbic acid 1 leads to nor-retinoic acid analogs 6.