Wen-Bin Yi

Direct Trifluoromethylthiolation and Perfluoroalkylthiolation of C(sp2)H Bonds with CF3SO2Na and RfSO2Na

A new method for CF3SO2Na-based direct trifluoromethylthiolation of C(sp(2))-H bonds has been developed. CF3SSCF3 is generated in situ from cheap and easy-to-handle CF3SO2Na, and in the presence of CuCl can be used for electrophilic trifluoromethylthiolation of indoles, pyrroles, and enamines. The method has been extended to perfluoroalkylthiolation reactions using RfSO2Na.

One-Pot Synthesis of 3,5-Disubstituted and Polysubstituted Phenols from Acyclic Precursors

A new strategy for the synthesis of 3,5-disubstituted phenols is established through one-pot Robinson annulation of α,β-unsaturated ketones with α-fluoro-β-ketoesters followed by in situ dehydrofluorination and tautomerization. This method has been extended to the synthesis of polysubstituted phenols and applied in the preparation of biologically active compounds.

Acid/Phosphide-Induced Radical Route to Alkyl and Alkenyl Sulfides and Phosphonothioates from Sodium Arylsulfinates in Water

A newly developed aqueous system with acid and phosphide was introduced in which odorless and stable sodium arylsulfinates can in situ generate arylsulfenyl radicals. These radicals have high reactivity to react with alkynes, alkenes, and H-phosphine oxides for the synthesis of alkyl and alkenyl sulfides and phosphonothioates. The control experiments and quantum calculations are also performed to gain insights into the generation mechanism of arylsulfenyl radicals. Notably, the chemistry is free of thiol odors, organic solvents, and metals.

Trifluoromethylation of thiophenols and thiols with sodium trifluoromethanesulfinate and iodine pentoxide

A selective and facile trifluoromethylation process for a wide range of thiophenols and thiols under metal free conditions has been developed using two simple and safe solids, sodium trifluoro-methanesulfinate and iodine pentoxide, via the radical process.

Organocatalytic One-Pot Asymmetric Synthesis of Thiolated Spiro-γ-lactam Oxindoles Bearing Three Stereocenters

The first asymmetric synthesis of spiro-γ-lactam oxindoles bearing three stereocenters is reported. One-pot thiol-Michael/Mannich/lactamization reactions promoted by a recyclable fluorous bifunctional cinchona alkaloid/thiourea organocatalyst afford products in moderate to good yields with up to 95% ee and 6:1 dr.

Radical-based regioselective cross-coupling of indoles and cycloalkanes

An investigation into the regiochemistry of radical functionalization of indoles using cycloalkanes through di-tert-butyl peroxide (DTBP)-promoted C(sp3)–H activation was conducted. A wide range of indoles bearing substituents at different positions was functionalized directly with simple cycloalkanes in moderate to high regioselectivity. 2-, 4- and 7-positions were mainly functionalized.

An odorless thia-Michael addition using Bunte salts as thiol surrogates

A newly developed C–S bond formation process via acid-catalyzed thia-Michael addition has been demonstrated. The protocol, in which Bunte salts generated from odorless and inexpensive sodium thiosulfate and organic halides are used as the thiol precursors, provides an efficient approach for the synthesis of β-sulfido carbonyl compounds.

Di-tert-butyl Peroxide Promoted Direct CH Arylation of Unactivated Arenes with Aryl Halides

Di‐tert‐butyl peroxide can smoothly promote the coupling of aryl halides with benzene derivatives without the aid of transition‐metal catalysts through a chain homolytic aromatic substitution mechanism in the presence of potassium tert‐butoxide.

Fluorous Lewis acids and phase transfer catalysts

The new phase-separation and immobilization technique known as fluorous biphase system (FBS) has become an active topic among researchers in both industry and academia. A series of fluorous biphasic reactions catalyzed by Lewis acid-type metal perfluorooctanesulfonates and metal bis(perfluorooctanesulfonyl)amides are reviewed in this paper. The recent development of fluorous phase transfer catalyst (PTC) is also discussed.

One-pot fluorination followed by Michael addition or Robinson annulation for preparation of α-fluorinated carbonyl compounds

Fluorination followed by the Michael addition or Robinson annulation of 1,3-dicarbonyl compounds is introduced for the synthesis of acyclic and cyclic α-fluoro-β-ketoesters and α-fluoro-1,3-diketones. The decarboxylation step can also be added to the reaction sequence. High efficiency is achieved by the microwave heating and atom economic one-pot synthesis.