473-08-5Relevant articles and documents
Synthesis of Homochiral α-Cyperone via Enantioselective Catalysis
Agami, Claude,Kadouri-Puchot, Catherine,Guen, Valerie Le
, p. 641 - 644 (1993)
The title sesquiterpene was obtained in a five-step synthesis starting from an achiral substrate: oxycarvone.Enantioselectivity is due to a phenylalanine-catalyzed intramolecular aldol reaction.
Scalable and sustainable electrochemical allylic C-H oxidation
Horn, Evan J.,Rosen, Brandon R.,Chen, Yong,Tang, Jiaze,Chen, Ke,Eastgate, Martin D.,Baran, Phil S.
, p. 77 - 81 (2016/06/01)
New methods and strategies for the direct functionalization of C-H bonds are beginning to reshape the field of retrosynthetic analysis, affecting the synthesis of natural products, medicines and materials. The oxidation of allylic systems has played a prominent role in this context as possibly the most widely applied C-H functionalization, owing to the utility of enones and allylic alcohols as versatile intermediates, and their prevalence in natural and unnatural materials. Allylic oxidations have featured in hundreds of syntheses, including some natural product syntheses regarded as € classics €. Despite many attempts to improve the efficiency and practicality of this transformation, the majority of conditions still use highly toxic reagents (based around toxic elements such as chromium or selenium) or expensive catalysts (such as palladium or rhodium). These requirements are problematic in industrial settings; currently, no scalable and sustainable solution to allylic oxidation exists. This oxidation strategy is therefore rarely used for large-scale synthetic applications, limiting the adoption of this retrosynthetic strategy by industrial scientists. Here we describe an electrochemical C-H oxidation strategy that exhibits broad substrate scope, operational simplicity and high chemoselectivity. It uses inexpensive and readily available materials, and represents a scalable allylic C-H oxidation (demonstrated on 100 grams), enabling the adoption of this C-H oxidation strategy in large-scale industrial settings without substantial environmental impact.
Stereoselective total synthesis of (-)-α-eudesmol, a P/Q-type calcium channel blocker
Aoyama,Araki,Konoike
, p. 1452 - 1454 (2007/10/03)
Practical and stereoselective total synthesis of (-)-αeudesmol 1, a P/Q-type calcium channel blocker, has been achieved with the key step being a cyclopropane ring opening accompanying introduction of a hydroxyl group. (+)-Carissone is used as a key intermediate.
An efficient asymmetric route to eudesmane acids. Total synthesis of (+)-12-hydroxy-α-cyperone, (+)-12-oxo-α-cyperone and (+)-3-oxoeudesma-4,11(13)-dien-12-oic acid
Xiong, Zhaoming,Yang, Jiong,Li, Yulin
, p. 2607 - 2612 (2007/10/03)
An efficient asymmetric synthesis of (+)-3-oxoeudesma-4,11(13)-dien-12-oic acid 4, (+)-12-hydroxy-α-cyperone 6 and (+)-12-oxo-α-cyperone 7 from (+)-dihydrocarvone 5 is described, which involves a novel diastereoselective preparation of (+)-α-cyperone 8.
An efficient and stereoselective synthesis of (+)-α-cyperone
Tenius, Beatriz S.M.,Rohde, Adrians R.,Victor, Mauricio M.,Viegas Jr., Claudio
, p. 197 - 203 (2007/10/03)
An efficient and stereoselective three step synthesis of (+)-α-cyperone 1 is described. The key step involves a stereoselective Michael addition of chiral imine to (R)-dihydrocarvone.
Relative and absolute configuration of allohedycaryol. Enantiospecific total synthesis of its enantiomer
Zhabinskii, Vladimir N.,Minnaard, Adriaan J.,Wijnberg, Joannes B. P. A.,De Groot, Aede
, p. 4022 - 4027 (2007/10/03)
The enantiomer of (+)-allohedycaryol, a germacrane alcohol isolated from giant fennel (Ferula communis L.), has been synthesized, thereby elucidating the relative and absolute stereochemistry of the natural product. The synthesis of (-)-allohedycaryol started from (+)-α-cyperone (5) which was available in relatively large quantities via alkylation of imine 7 derived from (+)-dihydrocarvone and (R)-(+)-1-phenylethylamine. In a number of steps 5 was converted into the mesylate 4 with a regio- and stereoselective epoxidation as the key step. A Marshall fragmentation of 4 was used to prepare the trans,trans-cyclodeca-1,6-diene ring present in allohedycaryol. The conformation of synthetic (-)-allohedycaryol was elucidated via photochemical conversion into a bourbonane system. The synthesis of (-)-allohedycaryol also showed that natural (+)-allohedycaryol has the opposite absolute stereochemistry to that normally found in higher plants.
A facile route to (-)-3-oxoeudesma-1,4,11(13)-trien-7αH-12-oic acid
Li,Chen,Shao,Li
, p. 2457 - 2462 (2007/10/02)
The first total synthesis of (-)-3-oxoeudesma-1,4,11(13)-trien-7αH-12-oic acid has been described. The key step is one-pot reaction involving dehydrogenation and allylic oxidation with selenium dioxide.
Lewis Acid catalyzed Diels-Alder Reactions of S-(+)-Carvone with Silyloxy Dienes. Total Synthesis of (+)-α-Cyperone.
Haaksma, Anja A.,Jansen, Ben J. M.,Groot, Aede de
, p. 3121 - 3130 (2007/10/02)
The Diels-Alder reactions of S-(+)-carvone with 2-trimethylsilyloxy-1,3-butadiene, 3-trimethylsilyloxy-1,3-pentadiene and 2-tert-butyldimethylsilyloxy-3-methyl-1,3-butadiene with ethylaluminium dichloride as catalyst are described.The synthetic value of the adducts is demonstrated by the total synthesis of (+)-α-cyperone from one of the adducts. Key Words: S-(+)-carvone, silyloxy dienes, Lewis acid catalysis, Diels-Alder reaction, (+)-α-cyperone
Practical Routes to Two Functionalized Decalones for the Synthesis of Quassinoids
Ziegler, Frederic E.,Hwang, Ki-Jun,Kadow, John F.,Klein, Scott I.,Pati, Uttam K.,Wang, Tein-Fu
, p. 4573 - 4579 (2007/10/02)
The chiral keto alcohol 6a was prepared from (S)-(+)-carvone.Because two steps in this process gave only modest yields of isolated materials, an alternative route was developed.Racemic keto alcohol 6b was prepared from enedione rac-13a by a more efficient process.
