Economic and practical advantages are offered by the iron(III)-catalyzed and air-mediated tandem coupling/hydroarylation/dehydrogenation of simple readily available aldehydes, alkynes, and amines for the synthesis of 2, 4-disubstituted quinolines (see scheme).

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A rearrangement reaction of propargylic aziridine, catalyzed by PPh(3)AuCl/AgOTf, forming trisubstituted and cycloalkene-fused pyrroles is described which involves an unusual tandem cyclization/ring-opening/Wagner-Meerwein process. The unique structures of the products demonstrated its potential applications for synthesizing structurally diverse alkaloids.

New aluminum-organophosphorus hybrid nanorods (AOPH-NR) have been prepared by reacting aluminum hydroxide (ATH) with dibenzylphosphinic acid (DBPA) with aluminum hydroxide (ATH) and used to prepare nanocomposites with epoxy resin. In order to determine the structure-property relationship of these composites, several other phosphinic acids of the general formula (R (CH 2 ) n ) 2 POOH (R ¼ ester, allyl, nitrile, n ¼ 1 or 2), and corresponding AOPHs were synthesized. FTIR, Raman, TGA, and XRD examinations showed that only AOPH-NR possesses a highly hybrid structure and high thermostability. SEM and TEM confirmed the nanorod morphology of AOPH-NR. The formation mechanism can be described as a decomposing-reforming process. This characteristic causes AOPH-NR to exhibit superior properties. Limiting oxygen index (LOI) determination and cone calorimeter analysis showed that the incorporation of only 4.25 wt% AOPH-NR remarkably improved the LOI value to as much as 28.0 and led to a 23% reduction in peak heat release rate (PHRR). Dynamic mechanical analysis (DMA) indicated that the mechanical properties of epoxy resin were also improved by incorporating AOPH-NR. In this way, the aluminum-organophosphorus hybridization via reacting ATH with specific organophosphinic acids shows promise as a means of improving flame retardancy and mechanical properties simultaneously. The thermal and anti-flaming properties of composites, combined with the properties of AOPHs, allowed us to discover the important role that the release and migration of phosphorus species plays in fire-retarding materials. This provides a new insight into the design of high-performance flame retardants.

Double-walled Al/P/Si hybrid decomposable nanorods, which have the silica coated aluminum phosphonate nanostructure, were in-situ prepared by thorough but ordered reconstruction of montmorillonite. The reconstruction was facilely performed through hydrothermal reaction of montmorillonite with diphenyl phosphoric acid. The forming process of nanorods involved the decomposition of montmorillonite, the repolymerization to generate aluminum phosphonates, the assembly via π-π stacking interactions to form 1D nanostructure, and the coating of silica on aluminum phosphonates nanorods. Interestingly, it was found that only layered silicates exhibited such reconstruction into hybrid nanorods. The decomposition of the nano-sized sandwich structure may lead to high reactive Si-O tetrahedral and a synergistic reaction process. The nanorods showed decomposability around 400 o C, producing nanoparticles mainly composed of aluminum silicates. Fire property test showed that epoxy/Al-Si-P hybrid nanorods nanocomposites exhibited outstanding flame retarding performance. One possible explanation for this is that nano-sized particles resulted from decomposition easily migrated to the surface of epoxy resins, consequently forming protective layers.