A novel catalyst-free addition reaction of thiols to silyl glyoxylates is developed in water, providing an efficient route for the synthesis of α-hydroxysilanes.

This study demonstrates the synthesis of one-dimensional (1D) crooked gold (Au) nanocrystals by an electrochemical method with surfactant. For example, the primary surfactant may be cetyltrimethylammonium bromide (CTAB), and the auxiliary surfactant may be tetradodecylammonium bromide (TTAB) with isopropanol (IPA) solvent. The formation of crooked Au nanocrystals was induced by aggregation of many small Au nuclei between the several large Au nanoparticles during growth, causing the small Au nuclei to link to the large Au nanoparticles forming crooked Au nanocrystals.Extensive and intensive investigation on gold (Au) nanoparticles in biology, nonlinear optical switching, the formation of a modified surface for surface-enhanced Raman scattering (SERS), immunoassay labeling, optical contrast agents and catalysis have demonstrated that the size and shape of nanoparticles strongly depend on physical and chemical properties, 1 thus highlighting the importance of developing a special shape for Au nanoparticles. Hence, adequately controlling the shape and size during nanoparticle synthesis is an emerging research topic. Many investigations have prepared specially shaped two-dimensional (2D) metal nanowires with network structure by using various methods, such as chemical reduction, 2 irradiation of an intense pulsed laser on Au nanoparticles with surfactant solution, 3 nanoparticle deposition within the porous template membrane, 4 laser ablation technique, 5 and electrodeposition. 6 A surfactant micelle serving as the template in an electrochemical system was recently demonstrated. 7 The advantages of this method include fairly simple preparation procedure and easily controllable dimensions of produced particles. This work presents the first example of crooked Au nanocrystals synthesized electrochemically in the presence of isopropanol (IPA) solvent with surfactant solution.Au nanoparticles were prepared electrochemically using a simple two-electrode cell with anodic oxidation and cathodic reduction. The actual experimental cell was housed in a standard 20 Â 80 mm 2 glass test tube. At dimensions of 30 Â 10 Â 0:5 mm 3 , Au plate and Pt plate were cut to form the anode and cathode, respectively. Electrodes in the cell were spaced 10 mm apart and held in place by Teflon spacers. A growth solution of 0.08 M cetyltrimethylammonium bromide (CTAB, Fluka, 98%) and deionized (DI) water in the typical synthesis was prepared. The 3 mL of CTAB, which served as the electrolyte of growth solution, was put in the test tube. A measured amount of powdered auxiliary surfactant with 30 mg (tetradodecylammonium bromide; TTAB, Fluka, 99%) was added to the tube, where it floated on the growth solution. A pipette was employed to add 0.2 mL of IPA solvent into the solution. The tube was then sonicated at 100 kHz for 5 min. The electrolysis was performed under constant ultrasonication at 100 kHz for 25 min. The typical current was set at 5 mA, and the temperature was held constant at 40 C. The resulting solution was centrifuged at 6500 rpm for...

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