Reaction Of Sulfur Ylides Research Articles

Synthesis of 1,1,3-Polyfunctionalized Cyclobutane Derivatives from the Reaction of Sulfur Ylides with Bicyclo[1.1.0]butanes.

1,1,3-Polyfunctionalized cyclobutane derivatives have been synthesized from sulfur ylides and bicyclo[1.1.0]butanes (BCBs). This protocol operates under mild reaction conditions without the need for catalysts, generally producing moderate to good yields of syn-addition derivatives with structural diversity. An unexpected intramolecular rearrangement mechanism has also been proposed.

Direct Synthesis of α-Ketothioamide Derivatives through a One-Pot Reaction of Sulfur Ylides, Nitrosobenzenes, and Thioacetic Acid.

A one-pot approach has been developed for the synthesis of α-ketothioamide derivatives from sulfur ylides, nitrosobenzenes, and thioacetic acid. This protocol is carried out under mild reaction conditions in generally moderate to excellent yields without any precious catalysts, affording the derivatives with structural diversity. Additionally, a possible mechanism for this chemical transformation is proposed.

Pd-Catalyzed [4 + 1] Annulation Strategy to Functionalized 4-Methyleneproline Derivatives.

A Pd-catalyzed formal [4 + 1] cycloaddition reaction of sulfur ylides and in situ-generated Pd-stabilized zwitterions offers a convenient route to a series of functionalized proline derivatives. The utility of this method is demonstrated by a gram-scale synthesis and chemoselective functionalization of a proline-based derivative.

Alternative Approach to Access 5-Hydroxy-1H-pyrrol-2-(5H)-ones from Base-Induced Tandem Intramolecular Cyclization of Sulfur Ylide with Ketones and 1,3-Hydroxy Rearrangement.

An easily adaptable protocol for the preparation of 5-hydroxy-1H-pyrrol-2(5H)-ones from readily available starting materials has been reported. The reaction of sulfur ylides with carbonyl compounds is a common approach to synthesizing epoxides. Alternatively, we have developed a method with mild reaction conditions wherein sulfur ylide underwent an intramolecular cyclization with a ketonic carbonyl group in a highly efficient way and was followed by 1,3-hydroxy rearrangement to produce 5-hydroxy-1H-pyrrol-2(5H)-ones in excellent yields. The present method offers a straightforward approach to synthesize 5-hydroxy-1H-pyrrol-2(5H)-ones from sulfur ylides without the aid of transition metal in one-pot operation, which involves sequential cyclization and rearrangement reaction. The formation of 5-hydroxy-1H-pyrrol-2(5H)-ones is supported by different spectroscopic techniques, including X-ray crystallographic data and 2D NMR studies (COSY, HSQC, HMBC, and DEPT).

Progress in <italic>N</italic>,<italic>N′</italic>-dioxide/metal complex-catalyzed asymmetricreactions of ylides

<p indent="0mm">Ylides, as inner salt molecules, possess the properties of high activity and diverse reactivity. They are attractive for their convenient synthesis of compounds containing heteroatom. On the other hand, privileged Feng <italic>C</italic>₂ symmetric <italic>N</italic>,<italic>N′</italic>-dioxide ligands can coordinate with plenty of main group metals, transition metals, and rare earth metals, offering the opportunity to efficiently catalyze more than 70 types of asymmetric reactions. In this article, the<italic>N</italic>,<italic> N′</italic>-dioxide/metal complexes-promoted asymmetric reactions of sulfur ylides, nitrium ylides and iodonium ylides were reviewed, including asymmetric addition, cycloaddition, rearrangement and domino reactions, through Lewis acid catalysis, bimetallic relay catalysis, and photocatalysis. The possible reaction mechanism including transition state was emphasized. Last, the challenges and prospects of the <italic>N</italic>,<italic>N′</italic>-dioxide/metal complex-promoted asymmetric reactions of ylides were discussed.

Transition metal-free [2,3]-sigmatropic rearrangement in the reaction of sulfur ylides with allenoates.

An unprecedented transition metal free [2,3]-sigmatropic rearrangement involving stabilized sulfur ylides and allenoates has been thoroughly established. The scope and utility of this reaction have been extensively studied resulting in C-C bond formation under mild conditions with greater than 20 examples reported. A highlight of the work is the simple and fully operational process that does not involve the use of carbenes or the associated hazardous and sensitive reagents. The reaction can be performed at room temperature and using an open flask. Interestingly, the new C-C bond formation reaction is gram scalable, and the obtained isomers are readily separable, affording interesting building blocks that can be used in the preparation of complex molecules.

Alkene Synthesis by Photo-Wolff-Kischner Reaction of Sulfur Ylides and N-Tosylhydrazones.

A visible-light-driven and room temperature photo-Wolff-Kischner reaction of sulfur ylides and N-tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E- and Z-olefinic stereochemistry in the products could be controlled with excellent stereoselectivity. A series of mechanistic studies support that the reaction should proceed through a radical-carbanion crossover pathway, specifically involving addition of photo-generated sulfur ylide radical cations to N-tosylhydrazones to form carbanions and subsequent Wolff-Kischner process.

(2 + 1 + 1 + 1)-Annulation Reactions of Aryldiazonium Tetrafluoroborates with Sulfur Ylides to Polysubstituted Pyrazoles.

Novel divergent domino annulation reactions of sulfur ylides with aryldiazonium tetrafluoroborates have been developed, affording various tetra- and trisubstituted pyrazole derivatives in moderate to good yields. Three molecules of sulfur ylides were applied as C1 synthon to construct the complex products with five new chemical bonds formed in these one-pot reactions.

Domino Annulation Reaction of Sulfur Ylides and Morita-Baylis-Hillman Carbonates of Isatins: Synthesis of Oxospiro[bicyclo[3.1.0]hexane-6,3'-indolin] Scaffolds.

A sequential [3 + 2]/[2 + 1] annulation domino reaction of crotonate-derived sulfur ylides and Morita-Baylis-Hillman carbonates of isatins for the construction of oxospiro[bicyclo[3.1.0]hexane-6,3'-indolin] scaffolds in moderate to good yields with almost 1:1 diastereoselectivity has been developed. Mild reaction conditions and readily accessible starting materials as well as excellent functional group compatibility render this transformation a powerful tool for the synthesis of spirocyclopropyloxindoles. A gram-scale synthetic procedure was also successfully carried out and a plausible reaction mechanism could be proposed.

Synthesis and Bacteriostatic Activities of Modified Flutriafol Derivatives

This study aimed to evaluate the preservative ability of modified flutriafol derivatives against decay fungi. The bacteriostatic effect of flutriafol on Trichoderma viride was not efficient as expected. Flutriafol was modified as a parent substrate to improve its broad spectrum performance. Six triazole compounds were synthesized by Friedel–Crafts reaction, oxygen–sulfur–ylide reaction, and ring-opening addition reaction. The structures of the target products were determined by 1H NMR and MS. Antibacterial and antileakage tests were performed to optimize the most efficient agents among triazole target products.

A facile and efficient [4 + 2] annulation reaction of sulfur ylides: access to N-fused benzimidazoles

The synthesis of N-fused benzimidazoles via sulfur ylides is first reported. The reaction system is facile and mild without a metal catalyst.

Divergent Domino Reactions of Sulfur Ylides: Access to Functionalized Six- and Seven-Membered Nitrogen-Heterocycles.

Divergent domino annulation reactions of sulfur ylides and azadienes were developed. A wide range of functionalized benzofuran-fused six- and seven-membered nitrogen-heterocyclic compounds were prepared in moderate to excellent yields under mild conditions. It is worth noting that the crotonate-derived sulfur ylides could be used as a novel C2 synthon or C3 synthon selectively by simply transforming the base.

Beyond sulfide-centric catalysis: recent advances in the catalytic cyclization reactions of sulfur ylides.

Great achievements in the asymmetric cyclization reactions of sulfur ylides have been reached by using chiral sulfides; however, this method usually suffers from the high loading of chiral sulfides. Over the past decade, new catalysis technologies beyond chiral sulfide-based catalysis have been gradually applied to the cyclizations of sulfur ylides. These technologies, including organocatalysis, organometallic catalysis and photocatalysis, can avoid the use of stoichiometric chiral pools and enable the development of new cyclization reactions of sulfur ylides. In this tutorial review, recent advances in this rapidly developing field will be highlighted with particular emphases on the catalytic mechanism and the development of new reactions, new reagents and new concepts.

Catalytic Asymmetric Synthesis of Chiral Dihydrobenzofurans through a Formal [4+1] Annulation Reaction of Sulfur Ylides and In Situ Generated ortho‐Quinone Methides

The first example of a catalytic asymmetric formal [4+1] annulation reaction between sulfur ylides and in situ generated ortho‐quinone methides (o‐QMs) is reported in this work. A C2‐symmetric chiral urea was identified to be the best H‐bonding catalyst, affording a wide range of chiral 2,3‐dihydrobenzofurans in high yields and moderate enantioselectivities [70–98 % yields, up to 89:11 e.r. (enantiomeric ratio)].

ChemInform Abstract: Sequential Annulation Domino Reaction of Sulfur Ylides and α,β‐Unsaturated Cyclic Ketimines: Synthesis of Cyclic 2‐Alkenyl Aziridines.

A sequential annulation domino reaction of sulfur ylides and α,β-unsaturated cyclic ketimines for the construction of cyclic 2-alkenyl aziridines has been developed. Readily accessible starting materials, a one-pot procedure, excellent functional group compatibility, and mild conditions make this transformation a powerful tool for the synthesis of cyclic 2-alkenyl aziridines.

Sequential Annulation Domino Reaction of Sulfur Ylides and α,β-Unsaturated Cyclic Ketimines: Synthesis of Cyclic 2-Alkenyl Aziridines.

A sequential annulation domino reaction of sulfur ylides and α,β-unsaturated cyclic ketimines for the construction of cyclic 2-alkenyl aziridines has been developed. Readily accessible starting materials, a one-pot procedure, excellent functional group compatibility, and mild conditions make this transformation a powerful tool for the synthesis of cyclic 2-alkenyl aziridines.

Developments of Corey-Chaykovsky in Organic Reactions and Total Synthesis of Natural Products

The reactions of sulfur ylides with carbonyl, olefin or imine compounds named as the Corey- Chaykovsky, provide oxiranes, cyclopropane or aziridine, respectively. In this report, we try to introduce this important name reaction and highlight a comprehensive overview on the applications of this useful reaction in synthetic organic chemistry and total synthesis of natural products. Keywords: Corey-Chaykovsky, epoxidation, dimethylsulfoxonium methylide, dimethylsulfonium methylide, organic and total synthesis.

ChemInform Abstract: Formal Asymmetric [4 + 1] Annulation Reaction Between Sulfur Ylides and 1,3‐Dienes.

AbstractFunctionalized cyclopentenes are conveniently obtained via stereoselective cyclopropanation reaction of sulfur ylides with 1,2‐dienes followed by in situ stereospecific MgI2‐promoted rearrangement of vinylcyclopropanes.

Formal [4 + 1] cycloaddition of o-quinone methides: facile synthesis of dihydrobenzofurans

An efficient and straightforward method for the rapid synthesis of 2-substituted dihydrobenzofurans has been developed via reaction of sulfur ylides with o-quinone methides (o-QMs).

Theoretical Study on the Mechanism of Stereoselective Synthesis of Oxazolidinones

Oxazolidinones can be synthesized through an organocatalytic cascade reaction of stable sulfur ylides and nitro-olefins. This process, sequentially catalyzed by thiourea and N,N-dimethylaminopyridine (DMAP), is theoretically studied using density functional theory by the continuum solvation model. It is shown that the rate- and stereoselectivity-determining step is the addition reaction of sulfur ylide to the nitro-olefin with two competing reaction channels. One channel is where the nitro-cyclopropane is generated first and then converted into isoxazoline N-oxide through a DMAP-catalyzed rearrangement. The other channel is the direct generation of the isoxazoline N-oxide intermediate. DMAP plays an important role in the reaction as a nucleophilic catalyst. The mechanism for the important rearrangement reaction proposed by Xiao et al. (J. Am. Chem. Soc. 2008, 130, 6946-6948) is not appropriate as the reaction energy barrier is too high; a 10-step mechanism determined by our theoretical calculations is more feasible as the energy barrier is becoming much less than that by Xiao. It is the first time that the Hofmann rearrangement involved in the cascade organocatalysis is confirmed by theoretical calculations. Our result of the stereoselectivity for the synthesis of oxazolidinones is in good agreement with the experiment.