CuO Nanoparticles as Effective Reusable Heterogeneous Catalyst for S‐Arylation Reactions

Copper(II) oxide nanoparticles have been synthesized from Cu(OAc)₂ via a simple hydrolysis route and were found to be an efficient and inexpensive catalyst for ligand free C? S cross‐coupling reactions of malononitrile? CS₂ adduct with various aryl halides. Aryl iodides and bromides, with electron‐withdrawing as well as electron‐releasing groups on the aromatic ring, undergo coupling reactions in good yields.     

Copper‐Catalyzed Synthesis of Alkynyl Hydrazones from Alkynes and Hydrazonyl Chlorides

A novel ligand‐free synthesis of alkynyl hydrazones via coupling reaction of hydrazonyl chlorides and terminal alkynes, catalyzed by CuI led to excellent yields.     

Copper‐Catalyzed One‐Pot Synthesis of N‐Sulfonylalkanimidoyl Thiocyanates from Sulfonyl Azides,Alkynes, and KSCN

Ketenimine intermediates generated by the addition of copper acetylides to sulfonyl azides are trapped by KSCN to afford N‐sulfonylalkanimidoyl thiocyanates in moderate‐to‐good yields.     

Copper‐Catalyzed Synthesis of 2H‐Thiopyran Derivatives from Alkynes,Sulfonyl Azides,Carbon Disulfide,and Malononitrile

A one‐pot synthesis of functionalized thiopyran derivatives via a Cu‐catalyzed multicomponent reaction of sulfonyl azides, arylacetylenes and dipotassium 2,2‐dicyanoethylene‐1,1‐dithiolate, generated from malononitrile and CS₂, has been developed. When alkylacetylenes were used as the terminal alkynes, N‐(alkanethioyl)‐N‐(2,2‐dicyanoethanethioyl)methanesulfonamides were obtained in good yields.     

Measurements of carbon monoxide mixing ratios in Houston using a compact high-power CW DFB-QCL-based QEPAS sensor

Measurements of carbon monoxide (CO) mixing ratios in Houston, Texas, during the period from May 16, 2013 to May 28, 2013 were performed using a sensitive, selective, compact, and portable quartz-enhanced photoacoustic spectroscopy (QEPAS)-based CO sensor employing a high-power continuous wave (CW) distributed feedback quantum cascade laser (DFB-QCL). The minimum detectable CO concentration was 3 ppbv for the strong, interference-free R(6) absorption line at 2,169.2 cm^?1 and a 5 s data acquisition time. The average CO concentration during the measurement period was 299.1 ± 81.4 ppb with observed minimum and maximum values of 210.5 and 4,307.9 ppb, respectively. A commercially available electrochemical sensor was employed in-line for simultaneous measurements to confirm the response of the CW DFB-QCL-based QEPAS sensor to variations of the CO mixing ratios. Moderate agreement (R ² = 0.7) was found between both sets of CO measurements.     

Microwave-assisted chemoselective copper-catalyzed amination of o-chloro and o-bromobenzoic acids using aromatic amines under solvent free conditions

Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported.Some of the advantages of this method are high chemoselectivity,short reaction times,ease of work up procedure and elimination of the need for acid protection.     

Copper-catalyzed S-arylation of tetramethylguanidine–heterocumulene adducts

The synthesis of a novel class of aryl bis(dimethylamino)methylenecarbamodithioates via a copper-catalyzed S-arylation reaction of 1,1,3,3-tetramethylguanidine–heterocumulene adducts is described.     

Copper‐Catalyzed N‐Arylation of Polysubstituted Pyridines Synthesized by the Novel Reaction of N‐Sulfonyl Ketenimine and Malononitrile‐Trichloroacetonitrile Adduct

In this study, we synthesized some new derivatives of N‐(4‐amino‐5‐cyano‐6‐(trichloromethyl)pyridin‐2‐yl)alkyl sulfonamides in the presence of a copper catalyst. A one‐pot reaction system was used, and four components participated in the process. These four components were sulfonyl azides, terminal alkynes, malononitrile, and trichloroacetonitrile. The reaction rate was increased by the use of copper (I) iodide as the catalyst and tetrahydrofuran was used as the solvent. We achieved the final compounds in moderate to good yields. Moreover, we converted “NH₂” side group to N‐aryl by the use of various aryl halide analogs in acetonitrile as the solvent, under mild reaction and at the room temperature.     

Synthesis of functionalized benzothiadiazine 1,1-dioxide derivatives via intramolecular CH activation reactions of trichloroacetamidine and benzenesulfonyl chloride

The synthesis of functionalized benzothiadiazine 1,1-dioxide derivatives was achieved through a novel three-component intramolecular CH activation reaction of trichloroacetonitrile, benzenesulfonyl chloride, and various primary amines. This reaction was performed in the presence of catalytic copper(I) and l-proline as the ligand in tetrahydrofuran at room temperature.     

Separation and Assay of Cholecalciferol in Vitamin A + D Ointment

Summary. In this paper two methods are presented. One involves the separation of cholecalciferol from a topical ointment. The other involves the assay of cholecalciferol in this ointment. The study was performed with normal-phase high performance liquid chromatography using a NP-L3 column and UV detection. Applying a mobile phase mixture containing n-hexane:2-propanol (99:1) a total separation was achieved within 15 min. For isolation and assay of cholecalciferol from an ointment (vitamin A + D), dissolution in n-hexane gave the highest recovery (>95%). The isolation and assay process can be performed within 3.5 h.