Synthesis and reactions of 3-alkylsulfanyl-1,3-dihydro-2,1-benzisothiazole 2,2-dioxides

Copper(i)-catalyzed [4 + 2] cycloaddition of aza-ortho-quinone methides with bicyclic alkenes

An efficient copper(i)-catalyzed [4 + 2] cycloaddition of aza-ortho-quinone methides (ao-QMs) and bicyclic alkenes to prepare tetrahydroquinoline-fused bicycles bearing multiple stereocenters in good yields is reported.

Recent advances in the application of Diels–Alder reactions involving o-quinodimethanes, aza-o-quinone methides and o-quinone methides in natural product total synthesis

This review summarizes recent advances in Diels–Alder reactions involving o-QDMs, o-QMs and aza-o-QMs. The power and potential of this strategy in organic synthesis and natural product total synthesis is highlighted.

Synthesis of 3,4,5-trisubstituted isoxazoles via 1,3-dipolar cycloaddition/SO2 extrusion of benzoisothiazole-2,2-dioxide-3-ylidenes with nitrile oxides

An straightforward synthesis of 3,4,5-trisubstituted isoxazole derivatives via 1,3-dipolar cycloaddtion/SO₂ extrusion of benzoisothiazole-2,2-dioxide-3-ylidenes with nitrile oxides is reported using 4 Å molecular sieves as dehydrochlorinating agent.

Synthesis and Reactions of Five-Membered Heterocycles Using Phase Transfer Catalyst (PTC) Techniques

Phase transfer catalysts (PTCs) have been widely used for the synthesis of organic compounds particularly in both liquid-liquid and solid-liquid heterogeneous reaction mixtures. They are known to accelerate reaction rates by facilitating formation of interphase transfer of species and making reactions between reagents in two immiscible phases possible. Application of PTC instead of traditional technologies for industrial processes of organic synthesis provides substantial benefits for the environment. On the basis of numerous reports it is evident that phase-transfer catalysis is the most efficient way for generation and reactions of many active intermediates. In this review we report various uses of PTC in syntheses and reactions of five-membered heterocycles compounds and their multifused rings.

Synthesis of benzo-γ-sultams via the Rh-catalyzed aromatic C–H functionalization of diazosulfonamides

Diazosulfonamides are first introduced and employed to synthesize 1-aryl-benzo-γ-sultams via Rh-catalyzed intramolecular aromatic C–H functionalization.