The Power of Iron Catalysis in Diazo Chemistry

AbstractThe use of iron catalysis to enable reactions with diazo compounds has emerged as a valuable tool to forge carbon–carbon or carbon–heteroatom bonds. While diazo compounds are often encountered with toxic and expensive metal catalysts, such as Rh, Ru, Pd, Ir, and Cu, a resurgence of Fe catalysis has been observed. This short review will showcase and highlight the recent advances in iron-mediated reactions of diazo compounds.1 Introduction2 Insertion Reactions2.1 Insertion into B–H Bonds2.2 Insertion into Si–H Bonds2.3 Insertion into N–H Bonds2.4 Insertion into S–H bonds3 Ylide Formation and Subsequent Reactions3.1 Doyle–Kirmse Rearrangement3.2 [1,2]-Stevens and Sommelet–Hauser Rearrangements3.3 Olefination Reactions3.4 Cycloaddition Reactions3.5 gem-Difluoroalkenylation4 Three-Component Reactions5 Miscellaneous6 Conclusion

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Recent Advances of 1,3,5-Triazinanes in Aminomethylation and Cycloaddition Reactions

Synthesis ◽

10.1055/s-0040-1707160 ◽

2020 ◽

Vol 52 (17) ◽

pp. 2469-2482

Author(s):

Jia-Rong Chen ◽

Dong Liang ◽

Wen-Jing Xiao

Keyword(s):

Reaction Mechanisms ◽

Short Review ◽

Cycloaddition Reactions ◽

Recent Advances ◽

Nitrogen Containing Compounds

1,3,5-Trisubstituted 1,3,5-triazinanes (hexahydro-1,3,5-triazines), as stable and readily available surrogates for formaldimines, have found extensive applications for the construction of various nitrogen-containing compounds. The formaldimines, formed in situ from this reagent class, can participate in various aminomethylation and cycloaddition reactions. This short review presents recent advances in this field with emphasis on the conceptual ideas behind the developed methodologies and the reaction mechanisms.1 Introduction2 Aminomethylations with 1,3,5-Triazinanes3 Cycloadditions with 1,3,5-Triazinanes3.1 Use of 1,3,5-Triazinanes as Two-Atom Synthons3.2 Use of 1,3,5-Triazinanes as Three-Atom Synthons3.3 Use of 1,3,5-Triazinanes as Four-Atom Synthons3.4 Use of 1,3,5-Triazinanes as Six-Atom Synthons4 Conclusions

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Recent Advances in the Tandem Cyclization/Cycloaddition of Allene Intermediates from Copper-Catalyzed Cross-Coupling of Diazo Compounds with Terminal Alkynes

Synthesis ◽

10.1055/s-0040-1705947 ◽

2020 ◽

Author(s):

Shiyong Peng ◽

Nuan Chen ◽

Min He ◽

Ting Zhou ◽

Yuqi Zhu ◽

...

Keyword(s):

Cross Coupling ◽

Short Review ◽

Diazo Compounds ◽

Terminal Alkynes ◽

Recent Advances ◽

Recent Developments ◽

Tandem Cyclization ◽

Cyclic Compounds

AbstractThis short review summarizes the most recent developments (since 2010) in the tandem cyclization/cycloaddition of allene intermediates, generated from the copper-catalyzed cross-coupling of diazo compounds with terminal alkynes, to afford cyclic compounds.1 Introduction2 Cyclization2.1 Cyclization with Nucleophiles2.2 Cyclization with Electrophiles2.3 6π-Electrocyclization2.4 Other Cyclization3 Cycloaddition4 Conclusion

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Indium(III)-Catalyzed Transformations of Alkynes: Recent Advances in Carbo- and Heterocyclization Reactions

Synthesis ◽

10.1055/s-0036-1588555 ◽

2017 ◽

Vol 49 (22) ◽

pp. 4931-4941 ◽

Cited By ~ 11

Author(s):

Nicklas Selander ◽

Stalin Pathipati ◽

Angela van der Werf

Keyword(s):

Transition Metal ◽

Environmentally Friendly ◽

Short Review ◽

Metal Catalysts ◽

Transition Metal Catalysts ◽

Nucleophilic Additions ◽

Terminal Alkynes ◽

Cyclization Reactions ◽

Recent Advances

The use of a well-chosen catalyst is instrumental for the development of more efficient, economical and environmentally friendly reactions. In recent decades, indium-based catalysts have proven to be competitive and useful alternatives to transition-metal catalysts such as silver and gold. In this short review, we present some of the recent advances in indium(III)-catalyzed transformations of alkynes, with a focus on cyclization reactions.1 Introduction2 Terminal Alkynes as Nucleophiles3 Nucleophilic Additions to Alkynes4 Carbo- and Heterocyclization Reactions4.1 Carbocyclization4.2 Oxygen-Based Heterocycles4.3 Nitrogen-Based Heterocycles4.4 Sulfur-Based Heterocycles5 Conclusion

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Recent Advances in Denitrogenative Reactions of Pyridotriazoles

Synthesis ◽

10.1055/s-0040-1707254 ◽

2020 ◽

Vol 52 (23) ◽

pp. 3564-3576 ◽

Cited By ~ 1

Author(s):

Ilya P. Filippov ◽

Gleb D. Titov ◽

Nikolai V. Rostovskii

Keyword(s):

Lewis Acids ◽

Heterocyclic Compounds ◽

Short Review ◽

Diazo Compounds ◽

Metal Compounds ◽

The Past ◽

Recent Advances ◽

Catalyzed Reactions ◽

Metal Catalyzed ◽

Chain Isomerization

AbstractDiazo compounds display versatile reactivity and therefore are widely used in organic synthesis. Diazo compounds bearing a 2-pyridyl or a related azine moiety on the diazo carbon exist in the form of fused 1,2,3-triazoles. In this short review, we summarize the recent advances in denitrogenative reactions of [1,2,3]triazolo[1,5-a]pyridines (‘pyridotriazoles’) and related fused 1,2,3-triazoles. Over the past decade, there has been a surge of activity in this field, with novel denitrogenative reactions of pyridotriazoles induced by metal compounds, light, and Brønsted and Lewis acids having been devised. As a result, heterocyclic compounds and functionalized α-picolines as well as bioactive molecules have been synthesized. In the review, emphasis is also placed on the mechanisms of the new reactions.1 Introduction2 Ring-Chain Isomerization of Pyridotriazoles3 Metal-Catalyzed Reactions3.1 Rh(II) Catalysis3.2 Rh(III) Catalysis3.3 Cu Catalysis3.4 Pd Catalysis3.5 Catalysis by Other Metals4 Metal-Free Reactions5 Conclusion

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Recent Developments in the Synthetic Uses of Silyl-protected Enoldiazoacetates for Heterocyclic Syntheses

Australian Journal of Chemistry ◽

10.1071/ch13576 ◽

2014 ◽

Vol 67 (3) ◽

pp. 365 ◽

Cited By ~ 14

Author(s):

Xinfang Xu ◽

Michael P. Doyle

Keyword(s):

Heterocyclic Compounds ◽

Biologically Active Compounds ◽

Biologically Active ◽

Diazo Compounds ◽

Cycloaddition Reactions ◽

Insertion Reactions ◽

Active Compounds ◽

The Core ◽

Recent Developments ◽

Metal Catalyzed

Diazo compounds have been used as precursors to a wide variety of heterocyclic compounds that represent the core structural subunits in many biologically active compounds. Various methodologies have been established for their synthesis via metal-catalyzed carbene transformations. Although the advantages of vinyldiazoacetates have been known for many years, realization of the synthetic use of enoldiazoacetates has been more recent. This review covers advances in the utility of silyl-protected enoldiazoacetates in heterocycle syntheses that include X–H insertion reactions, ylide rearrangements, formal [3+3]- and [4+3]-cycloaddition reactions, and other traditional and unusual metal carbene transformations.

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Biocatalytic and Chemo-Enzymatic Approaches for the Synthesis of Heterocycles

Synthesis ◽

10.1055/s-0040-1707210 ◽

2020 ◽

Author(s):

Daniele Castagnolo ◽

Fei Zhao ◽

Domiziana Masci ◽

Elena Tomarelli

Keyword(s):

Short Review ◽

Metal Catalysts ◽

Reaction Conditions ◽

Aromatic Heterocycles ◽

Recent Advances ◽

Aromatic Heterocyclic ◽

Enzymatic Methods

Heterocycles are ubiquitous structures in nature and can be found in many drugs and chemicals. Biocatalysts, alone or in combination with other metal catalysts, can be exploited for the construction of various heterocyclic rings under mild reaction conditions. This Short Review highlights the recent advances in the development of biocatalytic and chemo-enzymatic methods for the synthesis of both aliphatic and aromatic heterocyclic rings.1 Introduction2 Synthesis of Aliphatic Heterocycles2.1 Piperidines, Pyrrolidines and Piperazines2.2 Other Nitrogen-Containing Aliphatic Heterocycles2.3 Lactones and Lactams2.4 Other Oxygen-Containing Heterocycles3 Synthesis of Aromatic Heterocycles3.1 Pyrroles, Pyridines and Pyrazines3.2 Furans3.3 Bicyclic Aromatic Heterocycles4 Conclusion

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