Replacement of Less-Preferred Dipolar Aprotic and Ethereal Solvents in Synthetic Organic Chemistry with More Sustainable Alternatives

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(6), P. 6749 - 6794

Published: Feb. 24, 2022

Dipolar aprotic and ethereal solvents comprise just over 40% of all organic utilized in synthetic organic, medicinal, process chemistry. Unfortunately, many the common "go-to" are considered to be "less-preferable" for a number environmental, health, safety (EHS) reasons such as toxicity, mutagenicity, carcinogenicity, or practical handling flammability volatility. Recent legislative changes have initiated implementation restrictions on use commonly employed dipolar dimethylformamide (DMF) N-methyl-2-pyrrolidinone (NMP), ethers 1,4-dioxane. Thus, with growing legislative, EHS, societal pressures, need identify implement alternative that greener, safer, more sustainable has never been greater. Within this review, ubiquitous nature is discussed respect physicochemical properties made them so appealing chemists. An overview current being imposed discussed. A variety alternative, garnered attention past decade then examined, case studies examples where less-preferable successfully replaced safer highlighted. Finally, general guidance solvent selection replacement included Supporting Information review.

Language: Английский

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Counter Electrode Reactions—Important Stumbling Blocks on the Way to a Working Electro‐organic Synthesis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(47)

Published: June 7, 2022

Over the past two decades, electro-organic synthesis has gained significant interest, both in technical and academic research as well terms of applications. The omission stoichiometric oxidizers or reducing agents enables a more sustainable route for redox reactions organic chemistry. Even if it is well-known that every electrochemical oxidation only viable with an associated reduction reaction vice versa, relevance counter often less addressed. In this Review, importance corresponding highlighted how can affect performance selectivity electrolytic conversion. A selection common strategies unique concepts to tackle issue are surveyed provide guide select appropriate synthesis.

Language: Английский

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Transition metal–catalyzed remote C─H borylation: An emerging synthetic tool

Science Advances, Journal Year: 2023, Volume and Issue: 9(16)

Published: April 21, 2023

Transition metal–catalyzed C─H bond activation and borylation is a powerful synthetic method that offers versatile transformation from organoboron compounds to virtually all other functional groups. Compared the ortho-borylation, remote remains more challenging owing inaccessibility of these bonds. Enforcing metal catalyst toward bonds needs well-judged design through proper ligand development. This review article aims summarize recent discoveries for by employment new catalyst/ligand with help steric ligand, noncovalent interactions. It has been found now takes part in total synthesis natural products shorter route. Whereas, Ir-catalyzed predominant, cobalt also started affect this field sustainable cost-effective

Language: Английский

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Enantioselective palladaelectro-catalyzed C–H olefinations and allylations for N–C axial chirality

Chemical Science, Journal Year: 2021, Volume and Issue: 12(42), P. 14182 - 14188

Published: Jan. 1, 2021

Enantioselective palladaelectro-catalyzed C-H alkenylations and allylations were achieved with easily-accessible amino acids as transient directing groups. This strategy provided access to highly enantiomerically-enriched N-C axially chiral scaffolds under exceedingly mild conditions. The synthetic utility of our was demonstrated by a variety alkenes, while the versatility approach reflected atroposelective allylations. Computational studies insights into facile activation seven-membered palladacycle.

Language: Английский

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Synthesis of Spiro[benzo[d][1,3]oxazine-4,4′-isoquinoline]s via [4+1+1] Annulation of N-Aryl Amidines with Diazo Homophthalimides and O₂

Organic Letters, Journal Year: 2022, Volume and Issue: 24(6), P. 1280 - 1285

Published: Feb. 7, 2022

Synthesis of spiro[benzo[d][1,3]oxazine-4,4'-isoquinoline]s through a unique [4+1+1] annulation N-aryl amidines with diazo homophthalimides and O2 is presented. This unprecedented spirocyclization reaction features readily obtainable substrates, structurally pharmaceutically attractive products, cost-free clean oxygen source, sustainable medium, tolerance broad spectrum functional groups, an interesting mechanism based on sequential C(sp2)-H/C(sp3)-H bond cleavage insertion.

Language: Английский

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Cobaltaelectro-Catalyzed C–H Annulation with Allenes for Atropochiral and P-Stereogenic Compounds: Late-Stage Diversification and Continuous Flow Scale-Up

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(14), P. 9713 - 9723

Published: July 11, 2023

The 3d metallaelectro-catalyzed C-H activation has been identified as an increasingly viable strategy to access valuable organic molecules in a resource-economic fashion under exceedingly mild reaction conditions. However, the development of enantioselective is very challenging and its infancy. Here, we disclose merger cobaltaelectro-catalyzed with asymmetric catalysis for highly annulation allenes. A broad range C-N axially chiral P-stereogenic compounds were thereby obtained good yields up 98% high enantioselectivities >99% ee. practicality this approach was demonstrated by diversification complex bioactive drug well decagram scale electrocatalysis continuous flow.

Language: Английский

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Is Micellar Catalysis Green Chemistry?

Molecules, Journal Year: 2023, Volume and Issue: 28(12), P. 4809 - 4809

Published: June 16, 2023

Many years ago, twelve principles were defined for carrying out chemical reactions and processes from a green chemistry perspective. It is everyone’s endeavor to take these points into account as far possible when developing new or improving existing ones. Especially in the field of organic synthesis, area research has thus been established: micellar catalysis. This review article addresses question whether catalysis by applying reaction media. The shows that many can be transferred an solvent medium, but surfactant also crucial role solubilizer. Thus, carried much more environmentally friendly manner with less risk. Moreover, surfactants are being reformulated their design, degradation add extra advantages match all chemistry.

Language: Английский

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Metal-Catalyst-Free Radical Cyclization of 1,6-Enynes for the Selective and Switchable Synthesis of Lactams in Water

ACS Sustainable Chemistry & Engineering, Journal Year: 2022, Volume and Issue: 10(18), P. 6057 - 6062

Published: April 27, 2022

Three types of novel radical cyclization 1,6-enynes with sulfonyl hydrazides have been presented, which provided convenient synthetic approaches for accessing five-membered cyclic lactams, lactams containing C–I bond, and six-membered lactams. Notably, these transformations are implemented in metal-catalyst-free systems, three classes important lactam derivatives were synthesized selectivity controllability from the same substrate using water as green solvent.

Language: Английский

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Electrochemical Cage Activation of Carboranes

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(20)

Published: Feb. 11, 2022

Abstract Carboranes are boron–carbon molecular clusters that possess unique properties, such as their icosahedron geometry, high boron content, and delocalized three‐dimensional aromaticity. These features render carboranes valuable building blocks for applications in supramolecular design, nanomaterials, optoelectronics, organometallic coordination chemistry, neutron capture therapy (BNCT) agents. Despite tremendous progress this field, stoichiometric chemical redox reagents largely required the oxidative activation of carborane cages. In context, electrosyntheses represent an alternative strategy more sustainable syntheses. It is only recent few years considerable has been made electrochemical cage functionalization carboranes, which summarized Minireview. We anticipate electrocatalysis will serve increasingly powerful stimulus within current renaissance electrochemistry.

Language: Английский

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Sustainable Ruthenium(II)-Catalyzed C–H Activations in and on H₂O

ACS Sustainable Chemistry & Engineering, Journal Year: 2022, Volume and Issue: 10(21), P. 6871 - 6888

Published: May 17, 2022

Catalyzed C–H activation has surfaced as an enabling tool for molecular assembly, with a plethora of translational applications. The enormous developments toward the utilization ubiquitous bonds latent functionalities thus enabled efficient assembly increasingly complex scaffolds. Recently, paradigm shift occurred to enable sustainable, industry-relevant functionalization manifolds. Among most prominent transition metals activations, ruthenium offers several salient features, including cost-effective, robust, and mild activations unique reactivities remote functionalization. Indeed, ruthenium(II) catalysis by carboxylate assistance highly functional group tolerant predictable toolbox directed well nondirected functionalizations, major impact improve sustainability in industrial settings. These assets have allowed use nontoxic, nonflammable, cost-effective H2O reaction medium sustainable ruthenium(II)-catalyzed activations. In this perspective, we summarize potential water up February 2022.

Language: Английский

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