Transition Metal Catalyzed Azidation Reactions

A wide range of methodologies for the preparation of organic azides has been reported in the literature for many decades, due to their interest as building blocks for different transformations and their applications in biology as well as in materials science. More recently, with the spread of the use of transition metal-catalyzed reactions, new perspectives have also materialized in azidation processes, especially concerning the azidation of C–H bonds and direct difunctionalization of multiple carbon-carbon bonds. In this review, special emphasis will be placed on reactions involving substrates bearing a leaving group, hydroazidation reactions and azidation reactions that proceed with the formation of more than one bond. Further reactions for the preparation of allyl and vinyl azides as well as for azidations involving the opening of a ring complete the classification of the material.

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Monodentate Trialkylphosphines: Privileged Ligands in Metal-catalyzed Crosscoupling Reactions

Current Organic Chemistry ◽

10.2174/1385272824666200211114540 ◽

2020 ◽

Vol 24 (3) ◽

pp. 231-264 ◽

Cited By ~ 3

Author(s):

Kevin H. Shaughnessy

Keyword(s):

Transition Metal ◽

Cross Coupling ◽

Coupling Reactions ◽

Cross Coupling Reactions ◽

Aryl Bromides ◽

Wide Range ◽

Sterically Demanding ◽

Transition Metal Catalyzed ◽

Catalyzed Reactions ◽

Metal Catalyzed

Phosphines are widely used ligands in transition metal-catalyzed reactions. Arylphosphines, such as triphenylphosphine, were among the first phosphines to show broad utility in catalysis. Beginning in the late 1990s, sterically demanding and electronrich trialkylphosphines began to receive attention as supporting ligands. These ligands were found to be particularly effective at promoting oxidative addition in cross-coupling of aryl halides. With electron-rich, sterically demanding ligands, such as tri-tertbutylphosphine, coupling of aryl bromides could be achieved at room temperature. More importantly, the less reactive, but more broadly available, aryl chlorides became accessible substrates. Tri-tert-butylphosphine has become a privileged ligand that has found application in a wide range of late transition-metal catalyzed coupling reactions. This success has led to the use of numerous monodentate trialkylphosphines in cross-coupling reactions. This review will discuss the general properties and features of monodentate trialkylphosphines and their application in cross-coupling reactions of C–X and C–H bonds.

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Transition-Metal-Catalyzed Asymmetric Allylation of Carbonyl Compounds with Unsaturated Hydrocarbons

Synthesis ◽

10.1055/s-0036-1590986 ◽

2017 ◽

Vol 50 (05) ◽

pp. 956-967 ◽

Cited By ~ 14

Author(s):

Liu-Zhu Gong ◽

Pu-Sheng Wang ◽

Meng-Lan Shen

Keyword(s):

Transition Metal ◽

Carbonyl Compounds ◽

Building Blocks ◽

Asymmetric Allylation ◽

Unsaturated Hydrocarbons ◽

Homoallylic Alcohols ◽

Carbon Carbon Bonds ◽

Transition Metal Catalyzed ◽

Metal Catalyzed ◽

Direct Use

The asymmetric allylation of carbonyl compounds is an important process for the formation of carbon–carbon bonds, generating optically active homoallylic alcohols that are versatile building blocks with widespread applications in organic synthesis. The use of readily available unsaturated hydrocarbons as allylating reagents in the transition-metal-catalyzed asymmetric allylation has received increasing interest as either a step- or an atom-economy alternative. This review summarizes transition-metal-catalyzed enantioselective allylations on the basis of the ‘indirect’ and ‘direct’ use of simple unsaturated hydrocarbons (include dienes, allenes, alkynes, and alkenes) as allylating reagents, with emphasis on highlighting conceptually novel reactions.1 Introduction2 ‘Indirect’ Use of Unsaturated Hydrocarbons in Asymmetric Allylation of Carbonyl Compounds2.1 Enantioselective Allylation with 1,3-Dienes2.2 Enantioselective Allylation with Allenes2.3 Enantioselective Allylation with Alkenes3 ‘Direct’ Use of Unsaturated Hydrocarbons in Asymmetric Allylation of Carbonyl Compounds3.1 Enantioselective Allylation with 1,3-Dienes3.2 Enantioselective Allylation with Allenes3.3 Enantioselective Allylation with Alkynes3.4 Enantioselective Allylation with Alkenes4 Conclusions

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1,2-Dihaloalkenes in Metal-Catalyzed Reactions

Synthesis ◽

10.1055/s-0037-1610174 ◽

2018 ◽

Vol 50 (16) ◽

pp. 3087-3113 ◽

Cited By ~ 1

Author(s):

Benoit Daoust ◽

Nicolas Gilbert ◽

Paméla Casault ◽

François Ladouceur ◽

Simon Ricard

Keyword(s):

Transition Metal ◽

Building Blocks ◽

Facile Synthesis ◽

Bond Forming ◽

Bond Forming Reactions ◽

Transition Metal Catalyzed ◽

Catalyzed Reactions ◽

Metal Catalyzed

1,2-Dihaloalkenes readily undergo simultaneous or sequential difunctionalization through transition-metal-catalyzed reactions, which makes them attractive building blocks for complex unsaturated motifs. This review summarizes recent applications of such transformations in C–C and C–heteroatom bond forming processes. The facile synthesis of stereodefined alkene derivatives, as well as aromatic and heteroatomic compounds, from 1,2-dihaloalkenes is thus outlined.1 Introduction2 Synthesis of 1,2-Dihaloalkenes3 C–C Bond Forming Reactions4 C–Heteroatom Bond Forming Reactions5 Conclusion

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Trihaloethenes as versatile building blocks for organic synthesis

Organic & Biomolecular Chemistry ◽

10.1039/c6ob00091f ◽

2016 ◽

Vol 14 (24) ◽

pp. 5377-5389 ◽

Cited By ~ 4

Author(s):

Adriana S. Grossmann ◽

Thomas Magauer

Keyword(s):

Transition Metal ◽

Organic Synthesis ◽

Building Blocks ◽

Transition Metal Catalyzed ◽

Catalyzed Reactions ◽

Metal Catalyzed

Trihaloethenes are versatile C2-building blocks that can be simply modified via addition, elimination and transition metal-catalyzed reactions.

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Chemistry of Unsymmetrical C1-Substituted Oxabenzonorbornadienes

Current Organic Synthesis ◽

10.2174/1570179417666210105121115 ◽

2021 ◽

Vol 17 ◽

Author(s):

Austin Pounder ◽

Angel Ho ◽

Matthew Macleod ◽

William Tam

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Substituent Effects ◽

Face Selectivity ◽

Transition Metal Catalyzed ◽

Catalyzed Reactions ◽

Metal Catalyzed ◽

Synthetic Intermediate

: Oxabenzonorbornadiene (OBD) is a useful synthetic intermediate which can be readily activated by transition metal complexes with great face selectivity due to its dual-faced nature and intrinsic angle strain on the alkene. To date, the understanding of transition-metal catalyzed reactions of OBD itself has burgeoned; however, this has not been the case for unsymmetrical OBDs. Throughout the development of these reactions, the nature of C1-substituent has proven to have a profound effect on both the reactivity and selectivity of the outcome of the reaction. Upon substitution, different modes of reactivity arise, contributing to the possibility of multiple stereo-, regio-, and in extreme cases, constitutional isomers which can provide unique means of constructing a variety of synthetically useful cyclic frameworks. To maximize selectivity, an understanding of bridgehead substituent effects is crucial. To that end, this review outlines hitherto reported examples of bridgehead substituent effects on the chemistry of unsymmetrical C1-substituted OBDs.

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