Houben-Weyl. Methods of Organic Chemistry. Additional and Supplementary Volumes to the Fourth Edition. Volume E23k. Substance Index. Cyclic Compounds VII. Tricyclic Compounds I

The monapinone coupling enzyme (MCE), a fungal multicopper oxidase, catalyzes the regioselective C–C coupling between tricyclic monapinone A (the primary substrate) and other monapinones (secondary substrates) to produce atropisomeric biaryl homo- or heterodimers. In this study, mono-, bi- and tricyclic compounds were tested to determine whether they worked as secondary substrates for MCE. Among 14 cyclic compounds, MCE utilized semivioxanthin, YWA1, 1,3-naphthalenediol and flaviolin as secondary substrates to produce non-natural heterodimers. The atropisomeric biaryl heterodimers produced by MCE from monapinone A and semivioxanthin were isolated, and their structures were elucidated by NMR and MS. These findings indicate that MCE recognizes bi- and tricyclic compounds with a 1,3-dihydroxy or 1-hydroxy-3-methoxy benzene ring as a secondary substrate.

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Gold Vinylidenes as Useful Intermediates in Synthetic Organic Chemistry

Synthesis ◽

10.1055/s-0037-1611647 ◽

2019 ◽

Vol 51 (05) ◽

pp. 1087-1099 ◽

Cited By ~ 17

Author(s):

Fabien Gagosz

Keyword(s):

Organic Chemistry ◽

Short Review ◽

Gold Catalysis ◽

Migration Process ◽

Synthetic Organic Chemistry ◽

Cyclic Compounds ◽

Synthetic Approaches

Gold vinylidenes have recently emerged as useful intermediates in synthetic organic chemistry. These species, which can principally be accessed by a 1,2-migration process from a gold-activated alkyne or by dual gold catalysis on a diyne substrate, can react with nucleophilic partners or by C–H insertion to produce a variety of functionalized (poly)cyclic compounds. This short review covers the synthetic approaches developed so far to access gold vinylidenes and the different reactivities these species can exhibit.1 Introduction2 1,2-Migration Processes3 Dual Gold Catalysis4 Other Processes5 Conclusion

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N-Heterocyclic Carbene-Organocatalyzed Arene Formation: Application in Atroposelective Synthesis of Polysubstituted Benzenes

Synlett ◽

10.1055/s-0039-1690814 ◽

2020 ◽

Vol 31 (10) ◽

pp. 925-932 ◽

Cited By ~ 1

Author(s):

Tingshun Zhu ◽

Ke Xu ◽

Ziyuan Wang

Keyword(s):

Organic Chemistry ◽

Recent Work ◽

Organic Synthesis ◽

Heterocyclic Carbenes ◽

Powerful Method ◽

Recent Developments ◽

History Of ◽

Cyclic Compounds ◽

Near Future

In recent decades, organocatalysis by N-heterocyclic carbenes (NHCs) has emerged as a versatile and powerful method in organic synthesis. As a result of the power of NHC organocatalysis to produce cyclic compounds, polysubstituted benzenes, which are among the most important cyclic compounds in organic chemistry, can be synthesized efficiently and selectively. This article briefly summarizes the history of NHC organocatalysis, including recent developments in benzene-formation methods, and highlights our recent work in atroposelective arene formation by carbene-catalyzed formal [4+2] cycloadditions. We expect that more NHC-catalyzed methods for the synthesis of asymmetric arenes will be developed in the near future, providing shortcuts to syntheses of sophisticated chiral functional molecules with polysubstituted benzene nuclei.

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