Enantiospecific total syntheses of(–)-valeranone
نویسنده
چکیده
Two convenient methodologies have beendescribed for the enantiospecific synthesis of (–)-valeranone 1. The hydrindanone 12, obtained from the readily andabundantly available monoterpene (R)-carvone,has been converted into the ketoaldehyde 16via the alkene 15b. In anotherdirection the lactone 18, obtainedfrom the hydrindanone 12, has beenelaborated into the ketoaldehyde 16employing two methodologies. Intramolecular aldol condensation followed byhydrogenation transformed the ketoaldehyde 16into (–)-valeranone 1.
منابع مشابه
Protecting group free enantiospecific total syntheses of structurally diverse natural products of the tetrahydrocannabinoid family.
A simple, highly diastereoselective, Lewis acid catalyzed Friedel-Crafts coupling of a cyclic allylic alcohol with resorcinol derivatives has been developed. The method was applied for the enantiospecific total syntheses of structurally diverse natural products such as machaeriol-D, Δ(8)-THC, Δ(9)-THC, epi-perrottetinene and their analogues. Synthesis of both natural products and their enantiom...
متن کاملSynthesis of 3,4-dibenzyltetrahydrofuran lignans (9,9'-epoxylignanes).
Different strategies for the racemic or enantiospecific total syntheses of plant and mammalian 3,4-dibenzyltetrahydrofuran lignans are reviewed and compared. The multi-step approaches have various key step strategies: Diels-Alder reactions, Stobbe condensations, Michael additions, alkylations, nitrile oxide cycloadditions, radical cyclisations, dianion and oxidative couplings.
متن کاملFirst enantiospecific synthesis of the antitumor marine sponge metabolite (-)-15-oxopuupehenol from (-)-sclareol.
[reaction: see text] A new route toward puupehenone-related bioactive metabolites from (-)-sclareol, based on the palladium(II)-mediated diastereoselective cyclization of a drimenylphenol, is described. Utilizing this, the first enantiospecific synthesis of the antitumor and antimalarial (-)-15-oxopuupehenol, together with improved syntheses of (+)-puupehenone, (+)-puupehedione, and (+)-15-cyan...
متن کاملThe 9-phenyl-9-fluorenyl group for nitrogen protection in enantiospecific synthesis.
One of the biggest challenges in asymmetric synthesis is to prevent racemization of enantiopure starting materials. However, at least some of the enantiopurity is lost in most of the existing reactions used in synthetic organic chemistry. This translates into unnecessary material losses. Naturally enantiopure proteinogenic amino acids that can be transformed into many useful intermediates in dr...
متن کاملStereocontrolled Syntheses of Piperidine Derivatives Using Diastereoselective Reactions of Chiral 1,3-Oxazolidines with Grignard Reagents: Asymmetric Syntheses of the Pinidine Enantiomers.
Pinidine is the main constituent of Pinus sabiniana and related plant species as determined, along with its chemical structure, by Tallent and co-workers over 40 years ag0.1 The complete stereochemistry of pinidine was unambiguously established by Hill to be la, usmg chemical and spectroscopic methods.2 Very recently, further work on the pinidine alkaloid contents of pine (Pinus) and spruce (Pi...
متن کامل