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1.
para‐Substituted with electron donating or electron withdrawing groups triphenyl trithioarsenites, (ArS)3As, and octasulfur in refluxing carbon disulfide or chloroform do not give the triaryl tetrathioarsenates, (ArS)3As=S, as was claimed in the literature for tris(4‐methylphenyl) tetrathioarsenate. In some cases oxidative decomposition to As2O3 and disulfides ArSSAr was found. When equivalent amounts of the same esters and octasulfur were heated at 105 or 150 °C no AsV compound was detected or isolated and again some esters decomposed to As2O3 and disulfides. These experiments demonstrated that the aromatic trithioarsenites do not react with octasulfur, probably because they cannot open the octasulfur ring. These esters in solution react with octasulfur in the presence of a catalytic (10—20 mol%) amount of triethylamine giving disulfides, As2O3 and colored solids which could not be characterized. 相似文献
2.
Direct Introduction of a Dimesitylboryl Group Using Base‐Mediated Substitution of Aryl Halides with Silyldimesitylborane
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Dr. Eiji Yamamoto Kiyotaka Izumi Ryosuke Shishido Prof. Dr. Tomohiro Seki Noriaki Tokodai Prof. Dr. Hajime Ito 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17547-17551
The first dimesitylboryl substitution of aryl halides with a silylborane bearing a dimesitylboryl group in the presence of alkali‐metal alkoxides is described. The reactions of aryl bromides or iodides with Ph2MeSi?BMes2 and Na(OtBu) afforded the desired aryl dimesitylboranes in good to high yields and with high borylation/silylation ratios. Selective reaction of the sterically less‐hindered C?Br bond of dibromoarenes provided monoborylated products. This reaction was used to rapidly construct a D‐π‐A aryl dimesityl borane with a non‐symmetrical biphenyl spacer. 相似文献
3.
C? H Arylation of olefins by triarylphosphines via C? P bond cleavage has been achieved with either Pd0 or PdII catalysts. A variety of olefins and triarylphosphines are tolerated, and we inferred that both Pd0 and PdII could function directly without pre‐oxidation or pre‐reduction. 相似文献
4.
P. S. Khokhlov G. D. Sokolova V. N. Osipov N. F. Savenkov 《Russian Chemical Bulletin》1998,47(9):1768-1770
Exchange reactions of tetrathiophosphates with thiophosphoryl chloride were studied. The exchange of thiol groups between
compounds with tetracoordinated phosphorus centers proceeds at 150–220°C and results in the formation of dialkyl trithiochlorophosphates
and alkyl(aryl) dithiodichlorophosphates or their mixtures depending on the ratio of the reagents.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1815–1817, September, 1998. 相似文献
5.
Firouz Matloubi?MoghaddamEmail author Gholam R.?Koozehgiri Mohammad G.?Dekamin 《Monatshefte für Chemie / Chemical Monthly》2004,135(7):849-851
Summary. Combination of sodium saccharin and tetrabutylammonium iodide as a novel anionic catalyst system promotes selectively the trimerization of isocyanates to give symmetrical isocyanurates under solvent-free conditions.Present Address: College of Chemistry, Isfahan University of Technology, Isfahan, 84154, Iran 相似文献
6.
Maria N. Haikou Panayiotis V. Ioannou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):363-376
Triaryl trithioarsenites, (ArS)3As, are oxidized by air to As 2 O 3 and ArSSAr. In two cases the parent “thiol” (pyrid-2-thione and 1-hydroxypyrid-2-thione) is coproduced. The oxidation, in nonprotic solvents, is favored by electron-withdrawing groups at the para position of the phenyl group. The products obtained in nonprotic solvents were rationalized by assuming that the binding of the triplet dioxygen to arsenic(III) gives a triplet diradical, (ArS) 3 A?─O─?, or an arsenadioxirane, (ArS) 3 As(O 2 ), intermediate, which decomposes after nucleophilic attack by another (ArS) 3 As molecule. In protic solvents a zwitterion, (ArS) 3 As+─O─O?, and in the presence of moisture a hydroperoxy arsenic(V) compound, (ArS)3As(OH)─O─OH, may be intermediates in the air oxidation of some aromatic trithioarsenites. These data tend to indicate that arsenic(III) bound to suitable groups can directly bind dioxygen, a property which may have implications in chemotherapy and carcinogenesis. 相似文献
7.
合成了两个具有三个羟基的新型主体分子反式-5,10,15-三芳烃-5,10,15-三羟基-1-氢-三苯并[a,f,k]三茚(芳基分别为苯基和-萘基),并通过从头算对其及其异构体的结构进行了分析,结果发现当芳基为苯基时,其顺式异构体分子印环中所有原子不完全处于共平面,而其反式异构体和1-萘基的顺反异构体均处于共平面。 相似文献
8.
A series of 1,3,5‐triaryl‐1,5‐pentanediones was obtained via a sequential aldol condensation and Michael addition reaction in ionic liquid catalyzed by morpholine, as a one‐pot reaction. The significance of our findings relates to reducing the use of organic solvents, potentially toxic and hazardous materials, as well as its simplicity, good yields, mild conditions, and lower costs. 相似文献
9.
I2‐Catalyzed Divergent Regioselective Addition of Methoxybenzenes with Ethenylbenzenes under Microwave Irradiation
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Nalajala Nageswara Rao Maddi Raghavender Reddy Konakalla Ramakrishna Harshadas Mitaram Meshram 《Helvetica chimica acta》2014,97(5):744-749
A highly efficient synthesis of 1,2,2‐triarylethanones has been developed from simple and commercially available electron‐rich arenes and styrenes (ethenylbenzenes). 相似文献