The short history, specific features and future prospects of research of microbial metabolites, including antibiotics and other bioactive metabolites, are summarized. The microbial origin, diversity of producing species, functions and various bioactivities of metabolites, unique features of their chemical structures are discussed, mainly on the basis of statistical data. The possible numbers of metabolites may be discovered in the future, the problems of dereplication of newly isolated compounds as well as the new trends and prospects of the research are also discussed.

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Bioactive microbial metabolites.

3.7. Palladium Nanoparticles as Catalysts 888 3.8. Other Transition-Metal Complexes 888 3.9. Transition-Metal-Free Reactions 889 4. Applications 889 4.1. Alkynylation of Arenes 889 4.2. Alkynylation of Heterocycles 891 4.3. Synthesis of Enynes and Enediynes 894 4.4. Synthesis of Ynones 896 4.5. Synthesis of Carbocyclic Systems 897 4.6. Synthesis of Heterocyclic Systems 898 4.7. Synthesis of Natural Products 903 4.8. Synthesis of Electronic and Electrooptical Molecules 906

https://www.chem.ccu.edu.tw/~joyce/referance/ericyang/Chem.%20Rev/Chem.%20Rev.%202007,%20107,%20874-922.pdf

The Sonogashira Reaction: A Booming Methodology in Synthetic Organic Chemistry†

Microwave assisted organic synthesis-a review

6.4. Polyynes 3123 6.5. Using R-Hydroxy Stannanes 3124 6.6. Using the Hurtley Reaction 3124 6.7. Using a Methylenation Reaction 3125 7. Conclusions and Future Prospects 3125 8. Uncommon Abbreviations 3125 9. Acknowledgments 3125 10. Note Added in Proof 3125 11. References 3126 * Authorstowhomcorrespondenceshouldbeaddressed(evano@chimie.uvsq.fr, nicolas.blanchard@uha.fr). † Université de Versailles Saint Quentin en Yvelines. ‡ Université de Haute-Alsace. Chem. Rev. 2008, 108, 3054–3131 3054

Copper-mediated coupling reactions and their applications in natural products and designed biomolecules synthesis.

Catalytic transformation of ubiquitous C–H bonds into valuable C–N bonds offers an efficient synthetic approach to construct N-functionalized molecules. Over the last few decades, transition metal catalysis has been repeatedly proven to be a powerful tool for the direct conversion of cheap hydrocarbons to synthetically versatile amino-containing compounds. This Review comprehensively highlights recent advances in intra- and intermolecular C–H amination reactions utilizing late transition metal-based catalysts. Initial discovery, mechanistic study, and additional applications were categorized on the basis of the mechanistic scaffolds and types of reactions. Reactivity and selectivity of novel systems are discussed in three sections, with each being defined by a proposed working mode.

Transition Metal-Catalyzed C–H Amination: Scope, Mechanism, and Applications

Transition metal-catalyzed direct functionalization of C–H bonds is one of the key emerging strategies that is currently attracting tremendous attention with the aim to provide alternative environmentally friendly and efficient ways for the construction of C–C and C–hetero bonds. In particular, the strategy involving regioselective C–H activation assisted by various functional groups shows high potential, and significant achievements have been made in both the development of novel reactions and the mechanistic study. In this review, we attempt to give an overview of the development of utilizing the functionalities as directing groups. The discussion is directed towards the use of different functional groups as directing groups for the construction of C–C and C–hetero bonds via C–H activation using various transition metal catalysts. The synthetic applications and mechanistic features of these transformations will be discussed, and the review is organized on the basis of the type of directing groups and the type of bond being formed or the catalyst.

Transition metal-catalyzed C–H bond functionalizations by the use of diverse directing groups

A new method of cobalt-catalyzed synthesis of pyrrolidinones from aliphatic amides and terminal alkynes was discovered through a C-H bond functionalization process on unactivated sp(3) carbons with the silver cocatalyst using a bidentate auxiliary. For the first time, a broad range of easily accessible alkynes are exploited as the reaction partner in C(sp(3))-H bond activation to give the important 5-ethylidene-pyrrolidin-2-ones in a site-selective fashion. The reaction tolerates a wide variety of functional groups including -F, -Cl, -Br, -CF3, ether, cyclopropane, and thiophene. Both pyridine ligand and aromatic solvent play the important role for the promotion of reactivity. This cobalt-catalyzed cyclization reaction can be successfully extended to a variety of aromatic amides to afford a variety of isoindolinones. Attractive features of this catalytic system include its low cost, easy operation, and convenient access to a wide range of pyrrolidinones and isoindolinones.

Cobalt-Catalyzed Cyclization of Aliphatic Amides and Terminal Alkynes with Silver-Cocatalyst

Significance: Reported is a remarkable synthesis of 1,4-disubstituted and 1,4,5-trisubstituted 1,2,3-triazoles. The reaction of readily available N-tosylhydrazones with anilines is mediated by copper(II) and pivaloic acid. The reaction involves cyclization through C–N and N–N bond formation. This method enables an azide-free access to 1,2,3-triazoles with high efficiency under mild conditions. It exhibits a broad scope tolerating anilines with either electron-withdrawing or -donating groups and a variety of N-tosylhydrazones. More significantly, the two-step synthesis starting from aryl ketones to the desired triazoles can also be executed in a one-pot fashion without compromising the yield. An exclusive high regioselectivity – 1,4-disubstituted or 1,4,5-trisubstituted products – constitutes another advantage of this method. Comment: The most common route to build 1,2,3-triazoles is through Huisgen-type [3+2] cycloadditions. Although numerous methods for the improvement of the Huisgen reaction were reported recently, it is inevitable that an azide (which may sometimes not be readily available) will be involved. To the best of our knowledge, this paper is the first report to synthesize 1,2,3-triazoles without using toxic and potential explosive azide species. A possible tosylhydrazone intermediate (see structure above) of the reaction was proposed and synthesized. Its subsequent treatment with a catalytic amount of copper resulted in the formation of the expected produc. Examples of utilizing heterocyclic amines (e.g., 3-aminopyridine) as substrates in this reaction may be anticipated. Ar1 O

Zhanxiang Liu

Papers

Transition metal-catalyzed C–H bond functionalizations by the use of diverse directing groups

Cobalt-Catalyzed Cyclization of Aliphatic Amides and Terminal Alkynes with Silver-Cocatalyst

Copper-mediated synthesis of 1,2,3-triazoles from N-tosylhydrazones and anilines.

Nickel-catalyzed direct amination of arenes with alkylamines

Nickel-Catalyzed Direct Thioetherification of β-C(sp3)–H Bonds of Aliphatic Amides