Trienediolates of hexadienoic acids in synthesis. synthesis of retinoic and nor-retinoic acids.
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.
Trienediolates of hexadienoic acids in synthesis. Addition to unsaturated ketones. A convergent approach to the synthesis of retinoic acids
作者:Maria J. Aurell、Luisa Ceita、Ramon Mestres、Margarita Parra、Amparo Tortajada
DOI:10.1016/0040-4020(95)00114-n
日期:1995.3
The regioselectivity of the addition of the lithium trienediolates generated from hexa-2,4dienoic acids 1 and 2 or the dihydropyran-2ones 4 and 5 to unsaturated ketones 6 is studied. Equilibration conditions favour reaction of the trienediolates through their ω carbon, and the ketones according to 1,2- and 1,4-additions. β-Ionone 6a and the aryl-butenone 6b lead to the 1,2-ω-adducts 8, which undergo
A compound having the general structure of Formula (I):
or a pharmaceutically acceptable salt, solvate, or ester thereof, is useful in treating diseases, disorders, or conditions such as obesity, metabolic disorders, addiction, diseases of the central nervous system, cardiovascular disorders, respiratory disorders, and gastrointestinal disorders.
Rhodium-Catalyzed Synthesis of Eight-Membered Rings
作者:Brenton DeBoef、W. Richard Counts、Scott R. Gilbertson
DOI:10.1021/jo0620462
日期:2007.2.1
Experiments to develop a rhodiumcatalyst for the [4 + 2 + 2] cycloisomerization of dienynes with a second alkyne are described. The generality of the reaction is probed in terms of dienyne structure and alkyne structure. A catalystsystem that provides cyclooctatrienes in greater than 70% yield is reported. Several experiments to determine the nature of the catalyst are described.