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Herein, we report a protocol for PtI2-catalyzed formal three-component cascade cycloaddition reactions between γ-aminoalkynes and electron-deficient alkynes to afford highly substituted cyclohexadiene-b-pyrrolidines in good yields. On the basis of the results of the control experiments and density functional theory calculations, we present a plausible mechanism that proceeds via two key intermediates. The overall transformation involves the cleavage and formation of multiple C-C and C-N bonds and a previously unreported reaction mode of a seven-membered nitrogen heterocyclic intermediate.

An efficient catalytic asymmetric cascade cycloaddition reaction of arylalkynols with dioxopyrrolidines was developed. This reaction was achieved using Au(I) and (R)-BINOL-Ti(IV) bimetallic catalysts and exclusively delivered a series of chiral oxo-bridged bicyclic benzooxacine compounds in up to 86% yield with 96% ee as well as >33:1 dr. Meanwhile, three new σ bonds and three new stereogenic centers were formed in a one-pot process.

A cocatalyst-controlled divergent cascade cycloaddition reaction was developed for the synthesis of two different complex oxygen-containing heterocyclic compounds from arylalkynols and dioxopyrrolidienes in the presence of Au(I) catalyst. Using two different cocatalysts, Ni(OTf)2 and (rac)-phosphoric acid, two completely different products, spiroketals and oxa-bridged eight-membered cyclic ethers, were precisely constructed with high yields and good stereoselectivities, respectively. These methods feature simple and high efficiency, good chemoselectivity and mild conditions in one-pot.

Herein, we report a protocol for PtI

An efficient catalytic asymmetric cascade cycloaddition reaction of arylalkynols with dioxopyrrolidines was developed. This reaction was achieved using Au(I) and (

A yellow long persistent luminescence (LPL) phosphor of Sr3Ga4O9:Bi3+ were synthesized by a simple solid-state method. The luminescence properties have been investigated by photoluminescence (PL) spectra, LPL spectra, afterglow decay curves and thermoluminescence (TL) curves. A series of the excitation time and decay time dependent TL experiments have been conducted, and the trap characteristics of the phosphor were studied. The LPL can be detected more than 10 h, which is due to the fact that the feasible trap depth ensures the slow release of charge carriers. The results of LPL properties at variable temperature show that the phosphor has a broad application prospect in high-temperature environments.

Herein, we report an aryne triggered ring-opening fluorination protocol of a great variety of saturated sulfur heterocycles. A key factor for the success is the identification of a suitable mediator. Compared to previous methods, this transition-metal free protocol employs low-cost potassium fluoride as the fluorine source. The operational simplicity and mild reaction conditions allow for the rapid synthesis of a wide range of aliphatic fluoride compounds in good yields.