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171.
An efficient synthesis of alkyl bis(dimethylamino)methylenecarbamodithioates via a one-pot reaction between 1,1,3,3- tetramethylguanidine,carbon disulfide and substituted oxiranes,in good yields,is described.  相似文献   
172.
An efficient and novel method for the thioetherification of an alcohol with disulfides or NaSH under microwave irradiation is presented. In the presence of iodine, a variety of alcohols were smoothly S‐alkylated with disulfides or NaSH to give the corresponding thioethers in moderate to excellent yields.  相似文献   
173.
174.
A simple and efficient one‐pot synthesis of alkyl 2‐(alkyl)‐4‐methyl‐2‐thioxo‐2,3‐dihydrothiazole‐5‐carboxylates from the reaction of primary alkylamines and carbon disulfide in the presence of 2‐chloro‐1,3‐dicarbonyl compounds is described. This new protocol has several advantages such as lack of necessity of the catalyst, good yields, mild conditions and short times for reaction.  相似文献   
175.
Abstract

The synthesis and structure of the indium dithiocarbamate, In[S2CN(CH3)2]3·(1/2) 4-mepy (4-mepy=4-methylpyridine), is described. Indium metal was oxidized by tetramethylthiuram disulfide in 4-methylpyridine at 25°C to form a new, homoleptic indium(III) dithiocarbamate in yields exceeding 60%. In[S2CN(CH3)2]3 exists as a discrete molecule with a distorted-octahedral geometry. The compound crystallizes in the P 1 (No. 2) space group with a=9.282(1)Å, b=10.081(1)Å, c=12.502Å, α=73.91(1)°, β=70.21(1)°, γ=85.84(1)°, Z=2, V(Å)=1057.3(3), R=0.046 and Rw =0.061.  相似文献   
176.
崔莉凤  刘博 《色谱》2000,18(5):470-472
 用气相色谱法分离提纯食用香料甲基 2 甲基 3 呋喃基二硫醚 ,纯度 (质量分数 )达到 99.5%。分离柱为4%FFAP +1 %H3PO4ChromosorbW /AW DMCS(80目~ 1 0 0目 )不锈钢柱。用红外光谱、气相色谱 /质谱和核磁共振谱进行了结构鉴定。  相似文献   
177.
A trithiocarbonate RAFT agent was modified with a pyridyl disulfide group and used in the direct synthesis of endgroup pyridyl disulfide‐functionalized homo‐ and amphiphilic block copolymers of oligo(ethyleneglycol) acrylate (PEG‐A) and butyl acrylate (BA). Both the homo‐ and copolymerizations were found to be well controlled via the RAFT mechanism. The NMR analysis indicated that both the homopolymers of PEG‐A and the amphiphilic diblock copolymers of PEG‐A and BA possessed pyridyl disulfide terminal groups. A UV‐Vis absorption test revealed that the pyridyl disulfide endgroup of the polymer could be efficiently used to couple thiol‐bearing molecules to the polymer without the need for any post‐polymerization modification. This communication presents the first efficient direct synthesis of thiol‐reactive endgroup‐functionalized well‐defined polymers via the RAFT technique.

  相似文献   

178.
Carbamazepine (CBZ), as a typical pharmaceutical and personal care product (PPCP), cannot be efficiently removed by the conventional drinking water and wastewater treatment process. In this work, the CoS2/Fe2+/PMS process was applied for efficient elimination of CBZ. The CBZ removal efficiency of CoS2/Fe2+/PMS was 2.5 times and 23 times higher than that of CoS2/PMS and Fe2+/PMS, respectively. The intensity of DMPO-HO• and DMPO-SO4 followed the order of Fe2+/PMS < CoS2/PMS < CoS2/Fe2+/PMS, also suggesting the CoS2/Fe2+/PMS process has the highest oxidation activity. The effects of reaction conditions (e.g., CoS2 dosage, Fe2+ concentration, PMS concentration, initial CBZ concentration, pH, temperature) and water quality parameters (e.g., SO42, NO3, H2PO4, Cl, NH4+, humic acid) on the degradation of CBZ were also studied. Response surface methodology analysis was carried out to obtain the best conditions for the removal of CBZ, which are: Fe2+ = 70 µmol/L, PMS = 240 µmol/L, CoS2 = 0.59 g/L. The sustainability test demonstrated that the repeated use of CoS2 for 8 successive cycles resulted in little function decrease (<10%). These findings suggest that CoS2/Fe2+/PMS may be a promising method for advanced treatment of tailwater from sewage treatment plant.  相似文献   
179.
180.
Co-doped flower-like SnS2 was synthesized using a one-step hydrothermal method. The Co content of Co-doped SnS2 was facilely tuned by controlling the [Co]/[Sn] molar concentration ratio (SC-x; x = 0.05, 0.5, 1.0 2.0, where x indicates the [Co]/[Sn] ratio). The morphology of the samples did not significantly change despite changes in the Co dopant content. Compared to SC-0 (667 mV), SC-0.05 (400 mV), SC-0.5 (382 mV), and SC-1.0 (374 mV), SC-2.0 showed higher catalytic performance, with an overpotential of 323 mV at a current density of 10 mA/cm2 in 1 M KOH solution. Moreover, SC-2.0 exhibited high stability for 12 h during chronopotentiometry. SC-2.0 was unexpectedly transformed to weakly crystallized CoOOH nanoparticles after the stability test. The transformation rate from Co-doped SnS2 to CoOOH was decreased with an increase in the Co content.  相似文献   
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