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A new method for the synthesis of substituted 2-acylallylmetal reagents in a highly regio- and stereoselective fashion involving a three-component assembly of allenes, acyl chlorides, and bimetallic reagents (B-B, Si-Si, and Sn-Sn) catalyzed by phosphine-free palladium complexes is described. Treatment of various allenes (CR(2)R(3)=C=CH(2)) with acyl chlorides (R(1)COCl) and bispinacolatodiboron in the presence of PdCl(2)(CH(3)CN)(2) in toluene at 80 degrees C gave 2-acylallylboronates in moderate to good yields. The acylsilation of allenes with acid chlorides and hexamethyldisilane (5) proceeded successfully in the presence of Pd(dba)(2) in CH(3)CN affording the corresponding allylsilanes (CR(2)R(3)=C(COR(1))CH(2)SiMe(3)) in good to moderate yields. Several chloroformates (R(4)OCOCl) also react with 1,1-dimethylallene (2a) and 5 to afford allylsilanes (CR(2)R(3)=C(COOR(4))CH(2)SiMe(3)) in 66-70% yields. Acylstannation of allenes could also be achieved by slow addition of hexabutylditin (10) to the reaction mixture of acyl chloride (or chloroformate) and allene 2a in CH(3)CN in the presence of Pd(dba)(2) at 60 degrees C; the corresponding 2-substituted allylstannanes were isolated in moderate to good yields. The above catalytic reactions are completely regioselective and highly stereoselective. A mechanism is proposed to account for the catalytic reactions and the stereochemistry.

We have fabricated poly(3-hexylthiophene) organic field-effect transistors (P3HT-OFETs) with either high-temperature (200 C) thermally cured PVP gate dielectrics or low-temperature (120 C) photocured PVP gate dielectrics. We prepared the thermally cured PVP dielectric layer from a blend of poly(4-vinylphenol) (PVP) and poly(melamine-co-formaldehyde) (PMF); the photo-cured PVP dielectric formulation contained an additional photo-acid generator (PAG), which allowed the temperature for the cross-linking reaction to be reduced. We examined the intrinsic dielectric properties (e.g., the dielectric constant, the electrical insulating properties) and surface properties (e.g., morphology, surface energy) of the formulations loaded with various amounts of PAG (from 0 to 2.4 wt%). The P3HT-OFETs with the thermally cured PVP gate dielectrics exhibited an excellent carrier mobility of ca. 0.1 cm 2 V À1 s À1 , a sub-threshold swing of 2.0 V decade À1 , and an on/off ratio of 1.2 Â 10 4 . For comparison, the P3HT-OFET devices with the photo-cured PVP gate dielectrics also exhibited good electrical characteristics, including carrier mobilities as high as 0.06 cm 2 V À1 s À1 , sub-threshold swings as low as 1.4 V decade À1 , and on/off ratios as large as 3.0 Â 10 4 . To take advantage of the photocured PVP films, we also fabricated OFETs on a flexible, cheap ITO/PET substrate.

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Micro/nano-structured Mn 3 O 4 with an open three-dimensional flowerlike morphologywere fabricated by a facile solvothermal approach using hexadecyltrimethylammonium bromide used as surfactant and CH 3 CH 2 OH used as solvent. The Mn 3 O 4 microspheres are self-assembled by one-dimensional nanowires, and also, a dandelion-structure formation mechanism of the Mn 3 O 4 microspheres is discussed as well. The Mn 3 O 4 microspheres used as supercapacitor electrode in 1 mol L -1 Na 2 SO 4 electrolyte have a specific capacitance value of 286 F g -1 at a low current density of 0.5 A g -1 , and can still retain 80% (230 F g -1 ) and 73% (210 F g -1 ) when the current densities are increased by 10 times (5 A g -1 ) and 20 times (10 A g -1 ), respectively. In addition, the capacitance retention is 90% after 1000 cycles at a current density of 5 A g -1 . In comparison with data of Mn 3 O 4 synthesized in N,N-dimethylformamide solvent at 0.5 A g -1 and 5 A g -1 , the specific capacitance obtained is increased by 18.7% and 17.4%, respectively. 3 the present work is to achieve Mn 3 O 4 electrode material with high rate discharge-ability and get more insights to the formation mechanism of the micro/nano-structured structure. ExperimentalMn 3 O 4 microspheres were prepared by a solvothermal synthesis method and the experimental procedures were as follows: (1) CTAB (0.364 g) was dissolved in 40 ml CH 3 CH 2 OH and stirred for 15 min; (2) (Mn(CH 3 COO) 2 ·4H 2 O (2.45 g) was dissolved in 10 ml H 2 O; (3) Mn(CH 3 COO) 2 solution was added to CTAB solution and stirred for 30 min; (4) Carbamide (0.6g) was added and stirred for 30 min, followed by pouring into a 100 mL PTFE-lined stainless container, and subsequently heated at 140 ℃ for 4 h in a vacuum drying oven.The phase constituents were determined on a Rigaku D/max 2500pc X-ray diffractometer (XRD). X-ray photoelectron spectroscopy (XPS) was performed by ESCALAB 250Xi. The morphology of the synthesized materials was characterized by an S-4800 field emission scanning electron microscopic (FE-SEM). The microstructure of the sample mounted on a Cu grid was observed by a JEM-2100 at 200kV.Electrochemical measurements were performed in a three electrode system. The Mn 3 O 4 activated material was used as the working electrode which was prepared by mixing the activated material with acetylene black and PVDF at a mass ratio of 7:2:1 and the mass loading of each electrode is about 2 mg/cm 2 ; Pt electrode was used as the counter electrode, and Hg/Hg 2 Cl 2 electrode was used as the reference electrode in 1 mol L -1 Na 2 SO 4 electrolyte solution. The electrochemical performance was tested on a BTS-5V10 mA system in the range of 0-1V at 0.5 A g -1 and 5 A g -1 current densities. The electrochemical impedance spectroscopy (EIS) was conducted on a CHI 660E electrochemical workstation with an oscillation voltage of 5 mV and the applied Mn 3 O 4 electrode (205 F g -1 ) at a low current density of 0.5 A g -1 , while the specific capacitance (230 F g -1 ) is increased by about 72% than that of t...