Concise Total Synthesis of Agarozizanol B via a Strained Photocascade Intermediate
TLDR
In this paper, the prezizane-type sesquiterpene agarozizanol B was synthesized employing a photochemical cascade reaction as the key step.Abstract:
The prezizane-type sesquiterpene agarozizanol B was synthesized employing a photochemical cascade reaction as the key step. Starting from a readily available 1-indanone with a tethered olefin, a strained tetracyclic skeleton was assembled which contained all carbon atoms of the sesquiterpene with the correct relative configuration. The conversion into the tricyclic prezizane skeleton was accomplished by a strategic cyclopropane bond cleavage. Prior to the cyclopropane ring opening an adaption of the oxidation state was required, which could be combined with a reductive resolution step. After removal of two functional groups, the natural product was obtained both in racemic form or, if resolved, as the (+)-enantiomer which was shown to be identical to the natural product.read more
Citations
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The Awakening of a Sleeping Beauty: The ortho Photocycloaddition in the Total Synthesis of Protoilludane- and Prezizaene-Type Sesquiterpenes
Audrey Gilbert,Thorsten Bach +1 more
TL;DR: In this paper , an intramolecular ortho photocycloaddition of 7-(alkenyloxy)-indanones triggers a sequence of consecutive reactions that can lead in a single operation to the complete skeleton of two important classes of sesquiterpenes: protoilludanes and prezizaenes.
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Arene Activation through Iminium Ions: Product Diversity from Intramolecular Photocycloaddition Reactions
TL;DR: In this article , a meta photocycloaddition was observed which produced tetracyclic skeletons with five stereogenic centers in excellent regio− and diastereoselectivity.
Journal ArticleDOI
Photocycloadditions of benzene derivatives and their systematic application to organic synthesis
Arthur Desvals,Norbert Hoffmann +1 more
TL;DR: In this paper , a topological analysis permitting a systematic application of the [2 + 3] photocycloadditions to the total synthesis of natural products is presented and a selection of corresponding syntheses is discussed.
Journal ArticleDOI
ortho-Selective Dearomative [2π + 2σ] Photocycloadditions of Bicyclic Aza-Arenes.
Roman Kleinmans,Subhabrata Dutta,Kristers Ozols,Huilin Shao,Felix Schäfer,Constantin G. Daniliuc,Kendall N. Houk,Frank Glorius +7 more
TL;DR: In this paper , an ortho-selective intermolecular photocycloaddition of bicyclic aza-arenes including quinazolines, quinoxalines, and quinioxalines was presented.
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Total syntheses of strained polycyclic terpenes
Gleb A. Chesnokov,Karl Gademann +1 more
TL;DR: A number of recent examples of total syntheses of terpenoids with complex carbon frameworks featuring small rings are discussed in this article , with a focus on the new developments in strategical and tactical approaches to construction of such systems.
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