Silver colloidal nanorings have been synthesized by reducing silver ions with NaBH4 in trisodium citrate buffers. pH increase, by addition of NaOH, was used to speed up reduction reaction. The UV-vis absorption spectra of resulting silver nanorings showed two peaks accounting for transverse and longitudinal surface plasmon resonance, at ≈400 nm, and between 600 and 700 nm, respectively. The sha...

An efficient two-step method for the assembly of indanone derivatives starting from a simple vinyl arene has been developed. The sequence first involves addition of bis(pinacolato)diboron (B2 pin2 ) and N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) to a broad range of styrenes by utilizing IMesCuCl as catalyst. This step simultaneously accomplishes hydroboration of the alkene and ortho cya...

The conversion of α-benzocycloalkenones to homologous β-benzocycloalkenones containing six, seven and eight-membered rings is reported. This was accomplished via a Wittig olefination-oxidative rearrangement sequence using [hydroxy(tosyloxy)iodo]-benzene (HTIB) is the oxidant, that enables the synthesis of regioisomeric pairs of methyl-substituted β-benzocycloalkenones. The incorporation of carb...

The volatile oils from leaves of Michelia champaca L. collected bimonthly during one year (four times on the fifteenth day of January, March, May, July, September, and November 2004) were subjected to GC/FID and GC-MS analysis, from which thirteen components were identified. Additionally, part of the oil obtained from January collection was subjected to fractionation over silica gel soaked with...

In the present work, nanostructured porous silicon (nPSi) thin films were used as a substrate for deposition of green synthesized silver nanoparticles (AgNPs). Different kinds AgNPs by using Peumo extract and changing AgNO3 concentration. UV-vis spectroscopy confirmed success synthesis, TEM characterization showed with like-spherical shape an average diameter, which ranges from 4 to 25 nm, depe...

In recent years, nanoparticles of noble metals such as silver have gained enormous attraction owing to their distinct physical, chemical, and biological properties. the present study, (AgNPs) were synthesized from nitrate (AgNO3) using extracted chitosan reducing agent. The was exoskeleton marine crab Portunus pelagicus. Three different sample solutions prepared 0.02mM AgNO3 in 0.5% (w/v) chito...