The first catalytic asymmetric construction of the tryptanthrin skeleton has been established, taking advantage of a palladium(0)/chiral ligand-catalyzed enantioselective decarboxylative [4 + 2] cyclization of vinyl benzoxazinanones with isatins. This reaction has not only provided a direct and efficient method for constructing chiral tryptanthrin skeleta in high yields and excellent enantioselectivities (up to 97% yield, >99% ee) but also represents the first catalytic asymmetric decarboxylative cyclization of vinyl benzoxazinanones with isatins.

The first cyclization of para-quinone methide derivatives with alkynes was established by utilizing the [4 + 2] reaction of ortho-hydroxyphenyl-substituted para-quinone methides with ynones or benzyne, which efficiently constructed the scaffolds of chromene and xanthene in high yields (up to 88%). This protocol has not only fulfilled the task of developing cyclization reactions of para-quinone methide derivatives but also provided an efficient method for constructing chromene and xanthene scaffolds.

The first [4+3] cycloaddition of ortho-hydroxybenzyl alcohols has been established by making use of N,N'-cyclic azomethine imines as suitable 1,3-dipoles under Brønsted acid catalysis. By using this strategy, biologically important seven-membered heterocyclic scaffolds have been constructed in good yields and excellent diastereoselectivities (up to 92% yield, most >95 : 5 dr).

All-wet metal-assisted chemical etching (MACE) is a simple and low-cost method to fabricate one-dimensional Si nanostructures. However, it remains a challenge to fabricate Si nanocones (SiNCs) with this method. Here, we achieved wafer-scale fabrication of SiNC arrays through an all-wet MACE process. The key to fabricate SiNCs is to control the catalyst evolution from deposition to etching stages. Different from conventional MACE processes, large-size Ag particles by solution deposition are obtained through increasing AgNO3 concentration or extending the reaction time in the seed solution. Then, the large-size Ag particles are simultaneously etched during the Si etching process in an etching solution with a high H2O2 concentration due to the accelerated cathode process and inhibited anode process in Ag/Si microscopic galvanic cells. The successive decrease of Ag particle sizes causes the proportionate increase of diameters of the etched Si nanostructures, forming SiNC arrays. The SiNC arrays exhibit a stronger light-trapping ability and better photoelectrochemical performance compared with Si nanowire arrays. SiNCs were fabricated by using n-type 1–10 Ω cm Si(100) wafers in this work. Though the specific experimental conditions for preparing SiNCs may differ when using different Si wafers, the summarized diagram will still provide valuable guidance for morphology control of Si nanostructures in MACE processes.

An efficient dehydrative nucleophilic substitution reaction of C3-substituted2-indolylmethanols with azlactones has been established. In the whole process, Brønsted acid was supposed to activate two substrates simultaneously. A series of structurally diversified indole derivatives were obtained in generally good yields and high diastereoselectivities (up to 86% yield, >95:5 dr). This protocol not only provides a new strategy for the direct synthesis of structurally diversified indole derivatives, but also enriches the chemistry of 2-indolylmethanols via dehydrative substitution reaction.