Copper Nanoparticle Catalyzed Formation of C–S Bonds through Activation of S–S and C–H Bonds: An Easy Route to Alkynyl Sulfides­

Abstract

An efficient method for copper nanoparticle catalyzed ligand-free S-C sp bond formation was developed by using dimethyl sulfoxide as the solvent, a base, and molecular oxygen as a green oxidant. This study provides a new catalytic route for the production of alkynyl sulfides through dual activation of S-S and C-H bonds. A wide range of alkynyl sulfides were synthesized on a large scale with a low catalyst loading (0.5 mol% Cu). This synthetic methodology could also be extended to selenides, whereas tellurides underwent analogous reactions in the absence of a catalyst.

Getting Insights From Twitter: What People Want to Touch in Daily Life

“…As a content analysis technique, it is known that wordfrequency lists provide an overview of the words or phrases that occur in an analyzed text a certain number of times to identify the interest of the text. In addition, triangulation of the result with different queries [9], different analyses [17], and qualitative reviews of the sampled text [18] will help to strengthen the validity of the analysis. Following these methods to improve the reliability of the results, we used comprehensive queries in relation to the exploratory procedures to collect data, qualitatively review the text, and triangulate the results with multiple analyses.…”

“…This study focused on a Twitter survey for an investigation in Japan. In recent years, surveys using social media have been receiving increased attention for the light they shed on people's daily activities and moods [7], [8], [9], [10]. Among social media, Twitter [11] has the largest number of users in Japan.…”

Superhydrophobic and Low‐k Polyimide Film with Porous Interior Structure and Hierarchical Surface Morphology

“…constants of the poly(pyromellitic dianhydride-co-4,4′-oxydianiline) (PMDA-ODA) PI from 3.1 to 1.81. [14] The construction of a porous structure in the PI film also are reported to decrease the dielectric constant through the incorporation of air into the film. [15] Yabu et al fabricated honeycomb films with polyamic acid/ polyion complex and then prepared a lowk polyimide film through the imidization of polyamic acids [16] Kim et al synthesized porous films by placing polyimide precursors in a coagulation bath filled with a non-solvent by allowing the exchange of solvent with the nonsolvent to form the porous films.…”

Dynamical system approach of non-minimal coupling in holographic cosmology

“…The motivation for including a NMC term arises at the quantum level when quantum corrections to the scalar field theory are considered. This kind of NMC to gravity has been discussed enough in four dimensions [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41], in extra dimensions [42][43][44][45] and also in IG [46]. It turns out that in general relativity, the coupling constant is valued to 1/6 [47].…”