Jiangwei Wen

Catalyst-free direct arylsulfonylation of N-arylacrylamides with sulfinic acids: a convenient and efficient route to sulfonated oxindoles

A simple, efficient and catalyst-free procedure has been developed for the construction of sulfonated oxindoles via the direct arylsulfonylation of N-arylacrylamides with sulfinic acids. The present protocol, which simply utilizes cheap oxidants, readily-available starting materials, and catalyst-free conditions, provides an alternative and highly attractive approach to a series of sulfonated oxindoles with high atom efficiency and excellent functional group tolerance.

Metal-Free Oxidative Spirocyclization of Alkynes with Sulfonylhydrazides Leading to 3-Sulfonated Azaspiro[4,5]trienones

A novel and direct oxidative spirocyclization of arylpropiolamides with sulfonylhydrazides leading to 3-sulfonated azaspiro[4,5]trienones has been developed under metal-free conditions. The reaction is performed in a tandem manner constituted by the sequential sulfonylation of alkynes, ipso-carbocyclization, dearomatization, hydration, and oxidation processes, providing a convenient and efficient approach to various sulfonated azaspiro[4,5] trienones of biological importance.

Direct difunctionalization of alkynes with sulfinic acids and molecular iodine: a simple and convenient approach to (E)-β-iodovinyl sulfones

A simple and convenient approach for the construction of β-iodovinyl sulfones has been developed via direct difunctionalization of alkynes with sulfinic acids and molecular iodine. The present reaction provides a highly efficient approach to a diverse range of substituted (E)-β-iodovinyl sulfones in moderate to good yields with excellent stereo- and regio-selectivities but no need for any metal catalyst or additives.

Silver-catalyzed direct spirocyclization of alkynes with thiophenols: a simple and facile approach to 3-thioazaspiro[4,5]trienones

A new and convenient silver-catalyzed direct oxidative spirocyclization of alkynes with thiophenols is described. This methodology provides a simple and practical approach to various 3-thioazaspiro[4,5]trienones in moderate to good yields with high atom efficiency and excellent functional group tolerance.

Copper-catalyzed cyanoalkylarylation of activated alkenes with AIBN: a convenient and efficient approach to cyano-containing oxindoles

A novel, simple, and cost-effective copper-catalyzed direct cyanoalkylarylation of activated alkenes with AIBN has been developed with cheap K2S2O8 as the oxidant. A series of cyano-containing oxindoles that are otherwise difficult to obtain through previous methods were efficiently synthesized using this protocol.

Metal-Free Direct Hydrosulfonylation of Azodicarboxylates with Sulfinic Acids Leading to Sulfonylhydrazine Derivatives

Abstract A metal-free direct hydrosulfonylation protocol of azodicarboxylates with sulfinic acids has been developed for the construction of sulfonylhydrazine-1,2-dicarboxylates at room temperature. This methodology provides an efficient and practical approach to prepare various sulfonylhydrazine-1,2-dicarboxylates in good to excellent yields, which has the advantages of operation simplicity, environmental friendliness, high atom economy, and mild reaction conditions. GRAPHICAL ABSTRACT

Synergic TiO2 photocatalysis and guanine photoreduction for silver deposition amplification: An ultrasensitive and high-throughput visualized colorimetric analysis strategy for Anthrax DNAs in blood using wettable microwells array

An ultrasensitive and high-throughput visualized colorimetric method has been initially developed with a wettable microwells array for probing guanine base-containing anthrax DNAs in blood based on silver deposition amplified by the synergic TiO2 photocatalysis and guanine photoreduction under visible light. Hydrophilic microwells were first created on the hydrophobic slides to yield the wettable microwells array, on which photocatalytic titanium dioxide (TiO2) nanoparticles were deposited with dopamine (DA) to yield TiO2@DA for anchoring single strand DNA (ssDNA) capture probes without guanine bases. After the hybridization of the targeted anthrax DNAs, exonuclease I (Exo I) was introduced into the microwells to selectively digest the unhybridized ssDNA probes. The silver deposition was further conducted by the synergic photocatalysis of TiO2@DA and photoreduction of guanine bases of anthrax DNAs, thus achieving the amplified silver signals for the visualized colorimetric assays. Moreover, benefitting from the wettability feature of the hydrophilic-hydrophobic interfaces of the microwells array so fabricated, DNA analytes could be accumulated from the sample droplets through the condensing enrichment process to realize the ultrasensitive detection, in addition to circumventing any crossover contaminants between the sample droplets. The developed visualized colorimetric method with the microwells array was subsequently applied for probing anthrax DNAs in blood with levels down to 1.0 fM. DNAs with single-base and double-base mutations could also be identified accurately. Importantly, such a biosensing design route of a wettable microwells array, in combination with the photocatalytic silver deposition and specific Exo I-catalytic probe digestion, may promise extensive applications for the high-throughput, ultrasensitive, and selective detection of guanine-containing DNA targets with ultra-trace levels in complicated samples like blood.