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A general and efficient method for the direct alkynylation of unactivated C(sp3)–H bonds under metal-free conditions is described. The reaction performs smoothly under mild conditions and shows excellent functional-group tolerance. Initial mechanistic investigation indicates that the reaction may involve a radical pathway.

Herein we describe the first enantioselective Rh-catalyzed carboacylation of oximes (imines) via C–C activation. In this transformation, the benzocyclobutenone C1–C2 bond is selectively activated by a low valent rhodium catalyst and subsequently the resulting two Rh–C bonds add across a C═N bond, which provides a unique approach to access chiral lactams. A range of polycyclic nitrogen-containing scaffolds were obtained in good yields with excellent enantioselectivity. Further derivatization of the lactam products led to a rapid entry to various novel fused heterocycles.

A new prenylated xanthone, named mangostanate (I), is isolated from the pericarp of Garcinia mangostana.

The title reaction of in situ generated α-carbonyl iodides with terminal alkynes for the efficient α-alkenylation of ketones provides β,γ-iodoketones.

Photovoltaic technology has been presented with a great opportunity for development, owing to the recent and unprecedented rapid development of a new-type of solar cell based on organic–inorganic halide perovskites. Their power conversion efficiency (η) has surpassed 19% since the first perovskite-based solar cell (η = 3.8%) was reported in 2009. Moreover, this performance seems to be still far from fully optimized because of its versatile fabrication techniques and device configurations. In this review, the history of perovskites for photovoltaic applications and the landmark achievements to date are briefly outlined. Focusing on these new halide perovskite solar absorbers, the crystal structure, electronic structure, and intrinsic physical properties are systematically described, in an attempt to unravel the origins of superior solar cell performance. To meet the requirements of high-efficiency photovoltaics, the unique solar perovskite absorbers and electron and hole transport materials are discussed, as well as some unanswered questions and challenges facing their further development and commercialization.

The first total synthesis of the proposed structure of cycloinumakiol (I) and its C5 epimer (II) is presented.

Iron catalysis has been developed for the intermolecular 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes. The catalysis has a wide substrate scope and high functional-group tolerance. A variety of perfluoroalkyl iodides including CF3I can be employed. The resulting perfluoroalkylated alkyl and alkenyl iodides can be further functionalized by cross-coupling reactions. This methodology provides a straightforward and streamlined access to perfluoroalkylated organic molecules.

A range of diverse spirocycles are synthesized in good to excellent yields and many sensitive functional groups are tolerated.

Rhodium catalyzed isomerization of benzocyclobutenones having an propargyloxy substituent offers an unique approach to fused β-naphthol.

Single crystals of Sr8MgB18O36 are obtained by flux melting of SrCO3, MgO, H3BO3, and LiF (or NaF) in the molar ratio of 1:1:2:3.

The new title polyborate is synthesized by solid state reaction of stoichiometric mixtures of SrCO3, BeO, and H3BO3 (1253 K, 6 d) followed by spontaneous crystallization from a B2O3/NaF flux (melting, Pt crucible, 24 h, 10 K/d cooling rate).

Here we report the first highly enantioselective Rh-catalyzed carboacylation of olefins via C–C bond activation of benzocyclobutenones. Good yields and excellent enantioselectivities (92–99% ee, 14 examples) were obtained for substrates with various steric and electronic properties. In addition, fully saturated poly-fused rings were prepared from the carboacylation products through a challenging catalytic reductive dearomatization approach. These investigations provide a distinct way to prepare chiral carbon frameworks that are nontrivial to access with conventional methods.

A silver-catalyzed intramolecular oxidative aminofluorination of alkynes has been developed by using NFSI as a fluorinating reagent. This reaction represents an efficient method for the synthesis of various 4-fluoroisoquinolines and 4-fluoropyrrolo[α]isoquinolines.

Pd3Ag nanoparticles are prepared by dispersion of bulk Pd3Ag in liquid Li (Ni crucible, 250 °C, 4 h).

The silver-catalyzed fluorination has been developed for introducing a fluorine atom into organic compounds. Recent progress in this area is reviewed with an emphasis on the silver-catalyzed intramolecular aminofluorination of allenes.

A novel protocol A) is developed for the title reaction to give 4-fluoro-2,5-dihydropyrroles.

The preparation of title compounds (IX) is achieved by a three-step synthesis including multicomponent reaction to form tetrahydroquinolines (V), followed by cycloaddition with coumarin (VI) to afford oxazabicycles (VII).

It provides an effective method to prepare amines like (III) and (V) and pyrrolidines such as (VII) and (IX).

2-Aryltetrahydropyrroles are efficiently synthesized via a novel intramolecular oxidative aminofluorination of styrenes.

Three chiral β-hydroxy amide ligands were prepared by the reaction of benzyl chloride with amino alcohols derived from l -tyrosine. The titanium(IV) complex of chiral ligand 4a was found to be an effective catalyst for the asymmetric addition of methyl propiolate to aliphatic and aromatic aldehydes. The γ-hydroxy-α,β-acetylenic esters were obtained in excellent enantiomeric excesses (up to 94% ee) under optimized conditions.

The structure of Na2Al2B2O7 has been refined on X-ray powder diffraction data collected in transmission mode by Rietveld techniques because the polycrystalline samples exhibit a strong tendency of preferred orientation and the single crystals are of poor quality. Final refinement on powder diffraction data converged to agreement factors R-p=6.54%, R-wp=8.55% with R =5.24%. The title compound crystallizes in a trigonal space group P-31c. Lattice parameters are refined to be a=4.8113(1) Angstrom and = 15.2781(3) Angstrom. The structure consists of infinite [Al2B2O7](x) sheets stacking along c-axis and Na atoms in both the inter-sheets and intra-sheets. Infrared spectra of both Na2Al2B2O7 and Na2Ga2B2O7 are reported and a brief interpretation is given based on the structures. High quality X-ray powder diffraction data and results of thermal analysis are also presented. (C) 2001 Elsevier Science B.V. All rights reserved.

Copper-doped diamond-like carbon nanocomposite films have been facilely deposited by a liquid-phase electrochemical route from an acetonitrile solution of [Cu(CH(3)CN)(4)]ClO(4).