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A novel three-component Pd/norbornene cooperative catalysis cascade decarboxylative [2+2+2]/[2+2+3]cyclization of 4-iodoisoquinolin-1(2H)-ones and o-bromobenzoic acids or 8-bromo-1-naphthoic acid has been developed. The method affords a range of fused phenanthridinones and hepta[1,2-c]isoquinolinones and displays unique regioselectivity and broad substrate scope. Palladium/norbornene (Pd/NBE)-catalyzed C–H activation and subsequent decarboxylative coupling reactions were involved, and NBE acts as a building block for the construction of rigid nonplanar molecular architectures.

Three iridium complexes of (dfppy)2Ir(DAPB), (dfppy)2Ir(DAPB), and (dfppy)2Ir(DAPB) were synthesized by using phosphine carbonylimide derivative as auxiliary ligand and fluoro−/trifluoromethyl substituted 2‐phenylpyridine derivatives as primary ligands. Their quantum efficiency range from 19.4% to 38.5%, and show strong rigidochromic effect. The maximum emission wavelengths of solid‐state fluorescence have remarkable red shifts from 39 to 55 nm compared with these in CH2Cl2. Three novel iridium(III) complexes which exhibited strong rigidochromic effect with moderate internal quantum efficiencies were synthesized for organic optical functional materials. These complexes could blue‐light‐emitting in solvents and green‐light‐emitting in green.

Büchner reaction, as a unique type of expansive dearomatization, has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic precursors. Although the asymmetric version has been investigated since the early 1990s, enantioselective Büchner reaction is still limited by the catalyst type and substrate scope. This review aims to propose the limitation and possible development direction of this field by summarizing the evolution of catalytic asymmetric Büchner reaction, which is organized on the basis of intra- and intermolecular reactions. Considering the different metal carbene precursors, the reactions are further classified by carbene sources.

A copper-catalyzed oxidative cyclization of alkenyl N-propargyl ynamides is described. This protocol enables the practical synthesis of diverse spirocyclic γ-lactams bearing an exocyclic double bond with generally high Z/Eselectivity in moderate to good yields. Importantly, this copper-catalyzed oxidative cyclization demonstrates a distinctive selectivity in comparison with the related gold catalysis.

A new iridium(iii) complex Ir(tfmppy)2(tfmtpip) (1, tfmppy = 4-trifluoromethylphenyl-pyridine, tfmtpip = tetra(4-trifluoromethylphenyl)imidodiphosphinate) was synthesized and applied in organic light-emitting diodes (OLEDs). The devices with the structures of ITO/TAPC (1,1-bis[4-[N,N-di(p-tolyl)amino]phenyl]cyclohexane, 40 nm)/1(xwt%): mCP (N,N′-dicarbazolyl- 3,5-benzene, 20 nm)/TmPyPB (1,3,5-tri(m-pyrid-3-yl-phenyl)benzene, 40 nm)/LiF (1 nm)/Al (100 nm) exhibited a maximum power efficiency (ηp,max) of 113.23 lm W−1and a maximum current efficiency (ηc,max) of 115.39 cd A−1(0.01342 mA cm2) at the doping level of 5 wt%, which is among the best performances for Ir(iii) complex based OLEDs in the green-light-emitting region. Compared with our former work, the excellent device efficiencies are due to the use of TmPyPB as the electron-transporting/hole-blocking layer which has a relatively higher electron mobility than that of TPBi (2,2′,2′′-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)) and the introduction of the –CF3moiety to the Ir(iii) complex, which can increase the electron mobility of the complex. The device performances proved that the complex has potential applications as an efficient green emitter in OLEDs.

A highly efficient and eco‐friendly method for the tetramethylammonium iodide‐mediated sulfenylation/annulation of enaminones using thiosulfonates as the sulfenyl source was described under open‐air, metal‐, and oxidant‐free conditions. This method provides an alternative way of constructing C−S bonds, affords various substituted sulfenylated chromones in moderate to good yields, and shows broad substrate scope, and good functional group tolerance. Tetramethylammonium iodide(TMAI)‐promoted sulfenylation/annulation of enaminones using widely accessible thiosulfonates as the sulfenyl source was described under metal‐ and oxidant‐free conditions. These methods provide an alternative and facile synthetic route to access a series of 3‐sulfenylated chromones in moderate to good yields. This is a useful, time‐efficient, and scalable procedure for the construction of C(sp2)−S bonds.

Serine and glycine were used to combine with dimethyloldihydroxyethyleneurea (DMDHEU) as crosslinking agents to study the physical properties of the crosslinked fabrics and the reaction kinetics, and find that the bound nitrogen is in the series of DMDHEU ≫ DMDHEU‐serine > DMDHEU‐glycine at the same resin concentration. The results also show that the wet crease recovery angle (WCRA) value of the treated fabrics for the three crosslinking agent systems is in the series of DMDHEU‐serine > DMDHEU‐glycine > DMDHEU alone at a given dry crease recovery angle (DCRA). The DCRA values of the treated fabrics for DMDHEU alone are higher than those for DMDHEU‐α‐amino acids for a given value of tensile strength retention (TSR). WCRA values for the various treated fabrics is in the rank of DMDHEU‐serine > DMDHEU alone > DMDHEU‐glycine at the same TSR. Rate constants for the various crosslinking agents are in the series of DMDHEU‐glycine > DMDHEU‐serine > DMDHEU alone at the given heated temperatures. Energies needed to crosslink and the values of enthalpies and entropies of activation are all DMDHEU‐glycine > DMDHEU‐serine > DMDHEU alone. Infrared ray (IR) spectra strongly suggest the reaction between DMDHEU and serine and the reaction between the hydroxyl group (cellulose) and serine can occur in the pad‐dry‐cure process, but only a little for the latter. The reaction between the functional groups of serine and the aluminum ion to form a complex also confirm with IR spectrum. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 595–603, 2005

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