Facile synthesis of freestanding Si nanowire arrays by one-step template-free electro-deoxidation of SiO2 in molten salt

This communication presents a novel kind of silicon nanomaterial: freestanding Si nanowire arrays (Si NWAs), which are synthesized facilely by one-step template-free electro-deoxidation of SiO2 in molten CaCl2. The self-assembling growth process of this material is also investigated preliminarily.

Facile synthesis of Cu(II) complexes of monocondensed N,N,N donor Schiff base ligands: crystal structure, spectroscopic and magnetic properties

Four new copper(II) complexes, [((CuLN3)-N-1)(2)](ClO4)(2) (1), [(CuL2 N-3)(2)](ClO4)(2) (2), [CuL3(N-3)ClO4)](n) (3) and [CuL4(mu-1,1-N-3)(mu-1,3-N-3)(ClO4)](n) (4) where L-1 = N-1-pyridin-2-yl-methylene-propane-1,3-diamine, L-2 = N-1-(1-pyridin-2-yl-ethylidene)propane-1,3-diamine, L-3 =N-1-(1-pyridin-2-yl-ethylidene)ethane-1,2-diamine and L-4=N-1-(1-pyridin-2-yl-ethylidene)propane-1,2-diamine are four tridentate N,N,N donor Schiff base ligands, have been derived and structurally characterized by X-ray crystallography. Compounds 1 and 2 consist of double basal-apical end-on (EO) azide bridged dinuclear Cu-II complexes with square-pyramidal geometry. In complex 3 the square planar mononuclear [CuL3 (N-3)] units are linked by weakly coordinated perchlorate ions in the axial positions of Cu-II to form a one-dimensional chain. Two such chains are connected by hydrogen bonds involving perchlorate ions and azide groups. Compound 4 consists of 1-D chains in which the Cu-II ions with a square-pyramidal geometry are alternately bridged by single EO and end-to-end (EE) azido ligands, both adopting a basal-apical disposition. Variable temperature (300-2 K) magnetic susceptibility measurements and magnetization measurements at 2 K have been performed. The results reveal that complexes 1 and 2 are antiferromagnetically coupled through azido bridges (J= -12.18 +/- 0.09 and -4.43 +/- 0.1 cm(-1) for 1 and 2, respectively). Complex 3 shows two different magnetic interactions through the two kinds of hydrogen bonds; one is antiferromagnetic (J(1) = - 9.69 +/- 0.03 cm(-1)) and the other is ferromagnetic (J(2) = 1.00 +/- 0.01 cm(-1)). From a magnetic point of view complex 4 is a ferromagnetic dinuclear complex (J= 1.91 +/- 0.01 cm(-1)) coupled through the EO bridge only. The coupling through the EE bridge is practically nil as the N(azido)-Cu-II (axial) distance (2.643 angstrom) is too long. (C) 2006 Elsevier Ltd. All rights reserved.

Facile Synthesis of Koser`s Reagent and Derivatives from Iodine or Aryl Iodides

The first one-pot synthesis of neutral and electron-rich [hydroxy(tosyloxy)iodo]arenes (HTIBs) from iodine and arenes is presented, thereby avoiding the need for expensive iodine(III) precursors. A large set of including a polyfluorinated analogue, can be obtained from the corresponding aryl iodide under the same conditions. The reaction proceeds under mild conditions, without excess reagents, and is fast and high-yielding. Together, the two presented routes give access to a wide range of HTIBs, which are useful reagents in a variety of synthetic transformations.

Facile synthesis and characterization of ZrO2 nanoparticles prepared by the AOP/hydrothermal route

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Silver-gold nanotubes containing hot spots on their surface: facile synthesis and surface-enhanced Raman scattering investigations

We report the synthesis of silver-gold nanotubes containing hot spots along their surface. The Ag-Au nanotubes exhibited exceptional SERS properties compared to silver nanowires, enabling the detection of crystal violet in the 10(-10) M regime, as well as 9-nitroanthracene and benzo[a] pyrene at 3.3 x 10(-7) M.

Studies toward the construction of substituted piperidine-2-ones and pyridine-2-ones from Baylis-Hillman adducts: Discovery of a facile synthesis of 5-methyl-4-oxo-6-aryl-3-aza-bicyclo[3.1.0]hexane-1-carboxylates

Studies toward the construction of functionalised piperidone derivatives from derivatives of Baylis-Hillman adducts are described. Interestingly the 6-oxo-4-aryl-piperidine-3-carboxylates generated during the study serve as precursor for the facile synthesis of 4-oxo-6-aryl-3-aza-bicyclo[3.1.0]hexane-1-carboxylates

A Facile synthesis of 3-Methylene-4-aryl-1,3,4,5-tetrahydro-benzo[b][1,4] di-azepin-2-ones and 3-arylemethylene-4,5-dihydro-3H-benzo[b][1,4]diazepin-2-ylamines

A simple and convenient synthesis of 3-methylene-4-aryl-1,3,4,5-tetrahydro-benzo[b][1,4] diazepin-2-ones was accomplished by the SN2 nucleophilic substitution of the acetates of Baylis-Hillman adducts of acrylate with 1,2-phenylenediamines followed by base-mediated intramolecular cyclization. On the other hand similar substrates derived from the Baylis-Hillman adducts of acrylonitrile via Pinner’s reaction leads to 3-arylmethylene-4,5-dihydro-3H-benzo[b][1,4]diazepin-2-ylamines in good yields..

Facile Synthesis of Novel Functionalized Bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) Derivatives

An improved and efficient synthetic route to four functionalized bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF) derivatives 2−5 is reported. Tetrathiolate 1 was readily prepared from 2,2‘-bis(1,3,4,6-tetrathiapentalen-5-one) under carefully controlled conditions. Subsequent reaction of 1 with selected primary alkyl halides affords new functionalized BEDT-TTF derivatives in good yields.

Macrocycles and medicine - facile synthesis of a bis(macrocycle) with pendent functionality

The crystal structure of the Cu(II) perchlorate complex of a functionalised bis(rnacrocycle) ligand, where the individual macrocycle units are of the cyclam type and adopt the trans-III configuration, is analysed in terms of its possible relationship to those of bis(macrocycle) complexes possessing anti-viral activity. To cite this article: P V Bernhardt et al., C. R. Chimie 8 (2005). (C) 2004 Academie des sciences. Published by Elsevier SAS. All rights reserved.

Facile synthesis of rhodamine esters using acetyl chloride in alcohol solution

The rhodamines are a highly fluorescent class of compound used in many different fields of research, from the lasing medium in dye lasers to biological stains and markers for cellular drug resistance. In this study, esters (2-7) of rhodamine 110 (1) were conveniently prepared via the addition of acetyl chloride to a solution of the free acid (1) in the appropriate alcohol. This method conferred several advantages over previous preparations, namely that for low boiling alcohols, simple evaporation of the solution afforded the ester in quantitative yield with no need for purification. For higher boiling point alcohols, a method has been developed which allows the separation of longer chain esters from the alcohol solvent.

Organic reactions in ionic liquids: ionic liquid-accelerated facile synthesis of 3-alkyl-2,4-thiazolidinediones

The room temperature ionic liquid [bmim]PF6 is a new green solvent for the N-alkylation of 2,4-thiazolidinones. Significant rate enhancement and improved yields have been observed.

Hypervalent iodine in synthesis 92. A facile synthesis of 3-substituted-5,6-dihydroimidazo[2,1-b]thiazoles by cyclocondensation of alkynyl(phenyl)iodonium salts and imidazolidine-2-thione

A simple method for the synthesis of 3-substituted 5,6-dihydroimidazo[2,1-b]thiazoles is achieved by cyclocondensation of alkynyl(phenyl)iodonium salts with imidazolidine-2-thione.

Hypervalent Iodine in Synthesis. 94. A Facile Synthesis of 2-Substituted-imidazo[1,2-a]pyridines by Cyclocondensation of Alkynyl(phenyl) iodonium Salts and 2-Aminopyridine

A facile method for the synthesis of 2-substituted-imidazo[1,2-a]pyridines is achieved by cyclocondensation of alkynyl(phenyl)iodonium salts with 2-aminopyridine.

Hypervalent iodine in synthesis 93. A facile synthesis of 2-substituted imidazo[1,2-a]pyrimidines by cyclocondensation of alkynyl(phenyl)iodonium salts and 2-aminopyrimidine

Simple stirring of a mixture of the alkynyl(phenyl)iodonium salts 1 with 2-aminopyrimidine 2 in chloroform under reflux for two hours in the presence of K2CO3 gave, after workup, the 2-substituted imidazo[1,2-]pyrimidines 3 in moderate to good yields. A possible mechanism for the formation of 3 involves the intramolecular cyclization of the intermediate alkylidenecarbene 6.