Oxyphosphorodithiolation of Vinyl Azides with PS and Alcohols Leading to β-Keto Phosphorodithioates.

A simple strategy for the synthesis of β-keto phosphorodithioates has been developed through the direct oxyphosphorodithiolation of vinyl azides with PS and alcohols in the presence of water. The reaction is conducted at room temperature to provide a number of β-keto phosphorodithioates in moderate to good yields. This methodology has the advantages of simple operation, mild condition, broad substrate scope, and favorable group compatibility.

Metal-free visible-light-mediated aerobic nitrooxylation for the synthesis of nitrate esters with -BuONO.

A metal-free and sustainable visible-light-mediated method for the preparation of organic nitrate esters has been developed through the aerobic nitrooxylation reaction of α-diazoesters and cyclic ethers with -BuONO in the presence of dioxygen. This protocol provides an efficient approach to access nitrate esters with the advantages of clean energy, broad substrate scope, green oxidants, operational simplicity, and mild conditions.

Visible-Light Photoredox-Catalyzed Difunctionalization of Alkynes with Quinoxalin-2(1)-Ones, PS, and Alcohols.

Visible-light photoredox-catalyzed method has been developed for the synthesis of quinoxalin-2(1)-one-containing vinyl phosphorodithioates via direct difunctionalization of alkynes with quinoxalin-2(1)-ones, PS and alcohols. This four-component reaction could be carried out under metal-free and mild conditions, affording a number of quinoxalin-2(1)-one-containing vinyl phosphorodithioates in moderate to good yields with Z-isomers as the major products. Photocatalytic radical mechanism is proposed based on the results of radical trapping and fluorescence quenching experiments.

Visible-Light-Promoted Cascade Coupling of 2-Isocyanonaphthalenes with Elemental Sulfur and Amines to Construct Naphtho[2,1-d]thiazol-2-Amines.

A visible-light-induced strategy has been explored for the synthesis of naphtho[2,1-d]thiazol-2-amines through ortho-C-H sulfuration of 2-isocyanonaphthalenes with elemental sulfur and amines under external photocatalyst-free conditions. This three-component reaction, which utilizes elemental sulfur as the odorless sulfur source, molecular oxygen as the clean oxidant, and visible light as the clean energy source, provides a mild and efficient approach to construct a series of naphtho[2,1-d]thiazol-2-amines. Preliminary mechanistic studies indicated that visible-light-promoted photoexcitation of reaction intermediates consisting of thioureas and DBU might be involved in this transformation.

Copper-Catalyzed Three-Component Tandem Reaction of Alkynes, α-Diazo Esters, and TMSN to Access N-Substituted 1,2,3-Triazoles.

An efficient copper-catalyzed three-component tandem reaction of alkynes, α-diazo esters, and TMSN to construct triazoles has been developed. Through this strategy, a number of diverse N-substituted 1,2,3-triazoles were conveniently obtained in moderate to good yields from simple and readily available starting materials using KCO as the base. The mechanism of the tandem Cu-catalyzed azide-alkyne cycloaddition (CuAAC) and Cu-carbenoid-participated C-N coupling reaction has been investigated.

Visible-Light-Initiated Multicomponent Reactions of α-Diazoesters to Access Organophosphorus Compounds.

A simple visible-light-initiated strategy has been established for the construction of organophosphorus compounds via aerobic multicomponent reaction of α-diazoesters, cyclic ethers, and P(O)H compounds under air. A number of phosphonates and phosphinates could be efficiently isolated in moderate to good yields without the use of photosensitizers and metal reagents. This multicomponent reaction has advantages of mild condition, simple operation, eco-friendly energy, good functional-group tolerance, and gram-scale synthesis.

Metal-Free Trifluoroalkylation of Quinoxalin-2(1)-ones with Unactivated Alkenes and Langlois' Reagent.

A KSO-mediated three-component protocol has been developed for the construction of 3-trifluoroalkylated quinoxalin-2(1)-ones under metal-free conditions. The present reaction could be accomplished through the trifluoroalkylation of quinoxalin-2(1)-ones with unactivated alkenes and Langlois' reagent (CFSONa), which provided a highly attractive approach to access a series of biologically important 3-trifluoroalkylated quinoxalin-2(1)-ones.