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Aerogel, as the lightest solid, has attracted attentions all over the world due to its excellent properties. In this work, reduced graphene oxide (rGO)-tin oxide (SnO2) p-n heterojunction aerogels fabricated via a simple sol–gel method with graphene oxide (GO) and SnCl4·5H2O as the precursors was developed. Several analysis techniques (XPS, XRD, TGA, Raman, SEM, TEM etc.) were utilized to characterize the resulting aerogels, and the analysis data demonstrated the excellent mesoporous materials with low density (51–79 mg cm−3) and large specific surface area (278–431 m2 g−1). And p-type rGO sheets connected with n-type SnO2 nanoparticles directly affect the electrical properties of the resulting heterojunction aerogels. Based on these excellent properties, the rGO/SnO2 aerogel with excellent thermal stability was developed for the detection of phenol at room temperature. Delightedly, this sensor exhibited excellent sensitivity, repeatability and stability to phenol with a linear relationship in the range of 10–80 ppb.

A simple and highly efficient method for the rearrangement of bromohydrins mediated by Et 2Zn to synthesize carbonyl compounds was described. Various beta-bromo alcohols were treated with 0.6 equiv of Et 2Zn to form a zinc complex in CH 2Cl 2 at room temperature for 2 h, followed by 1,2-migration to give the corresponding carbonyl compounds. This remarkable and clean rearrangement is general for acyclic and cyclic bromohydrins, and a variety of ring-expansive and -contractive carbonyl compounds were obtained in good to excellent yields according to the feature of the starting bromohydrins. The functional group tolerance of organozinc reagents in this reaction will be useful in organic synthesis. The scope and limitations of this rearrangement process were also investigated.

Monosubstituted acetylenes were iodinated to form iodoacetylenes under simple conditions. Reaction of aryl acetylenes with molecular iodine in the presence of 4‐dimethylaminopyridine (DMAP) gave the desired products in good to excellent yields. Iodination of aryl acetylenic ketones using K2CO3 as base was also described.

A new and efficient methodology has been developed for the synthesis of beta-diketones from aromatic alpha-bromo ketones in the presence of Furukawa reagent under mild conditions. The present transformation is proposed to proceed via a Reformatsky-type reaction of alpha-bromo ketones, followed by C-C bond sigmatropic rearrangement of the aldolate intermediate to give beta-diketones in moderate to good isolated yields, while aliphatic alpha-bromomethyl ketones resulted in the formation of 2,4-disubstituted furans or cis-1,2-disubstituted cyclopropanols in moderate yields. The scope of this process was investigated, and a tentative mechanism was proposed.

Cycloadditions of alkynyl ketones with N-tosylimines catalyzed by Lewis bases to synthesize azetidines and pyrrolidines were systematically described. In the reaction of alkynyl ketones with N-tosylimines catalyzed by Bu 3 P at room temperature in toluene, highly functionalized pyrrolidines were formed in good to excellent yields. When DMAP was used in place of Bu 3 P as catalyst to facilitate the cycloaddition, completely substituted azetidines were produced in moderate to good yields in CH 2 Cl 2 . Both cyclization reactions proceeded smoothly with complete stereoselectivity. The scope and limitations of these cycloadditon reactions were also investigated.

A simple and highly efficient method for the rearrangement of bromohydrins mediated by Et2Zn to synthesize carbonyl compounds was described. Various β-bromo alcohols were treated with 0.6 equiv of Et2Zn to form a zinc complex in CH2Cl2 at room temperature for 2 h, followed by 1,2-migration to give the corresponding carbonyl compounds. This remarkable and clean rearrangement is general for acyclic and cyclic bromohydrins, and a variety of ring-expansive and -contractive carbonyl compounds were obtained in good to excellent yields according to the feature of the starting bromohydrins. The functional group tolerance of organozinc reagents in this reaction will be useful in organic synthesis. The scope and limitations of this rearrangement process were also investigated.

Monosubstituted acetylenes were iodinated to form iodoacetylenes under simple conditions. Reaction of aryl acetylenes with molecular iodine in the presence of 4‐dimethylaminopyridine (DMAP) gave the desired products in good to excellent yields. Iodination of aryl acetylenic ketones using K2CO3 as base was also described.

A new and efficient methodology has been developed for the synthesis of beta-diketones from aromatic alpha-bromo ketones in the presence of Furukawa reagent under mild conditions. The present transformation is proposed to proceed via a Reformatsky-type reaction of alpha-bromo ketones, followed by C-C bond sigmatropic rearrangement of the aldolate intermediate to give beta-diketones in moderate to good isolated yields, while aliphatic alpha-bromomethyl ketones resulted in the formation of 2,4-disubstituted furans or cis-1,2-disubstituted cyclopropanols in moderate yields. The scope of this process was investigated, and a tentative mechanism was proposed.