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In the present study, the reaction of thiols with alkyl sulfonyl halides was carried out in a nitrogenous base to compare the reactivity of ‐SH with that of ‐OH, which, however, led to the formation of disulfides. The reaction achieved as a result offers the use of an inexpensive reagent, quantitative yields of the product, and simplicity for the formation of the S‐S bond.  相似文献   
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New homologous ammonium-, pyridinium-, and pyrrolidinium-based sulfonamido functionalized ionic liquids have been synthesized in two steps using monoethanolamine, methanesulfonyl chloride, and tosyl chloride as precursors with ethanol as solvent. Attempts to synthesize dual amino functionalized ionic liquid containing both a primary and a secondary amine group in the same ionic liquid are also reported. All functionalized ionic liquids were characterized by 1H and 13C NMR. Melting point and thermal stability of the functionalized ionic liquids were measured by differential scanning calorimetry and thermogravimetric analysis.  相似文献   
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The specific rates of solvolysis of methanesulfonic anhydride have been measured conductometrically at ?10 °C in 41 solvents. Use of the extended Grunwald–Winstein equation, with the NT scale of solvent nucleophilicity and the YOTs scale of solvent ionizing power, leads to sensitivity to changes in solvent nucleophilicity (? value) of 0.95 and a sensitivity to changes in solvent ionizing power (m value) of 0.61, with a multiple correlation coefficient (R) of 0.973. Product selectivity values (S) in binary hydroxylic solvents favor alcohol attack in EtOH–H2O (a value of 1.2 in 90% EtOH rising to 4.0 in 40% EtOH) and in MeOH–H2O (a value of 3.7 in 90% MeOH rising to 6.0 in 50% MeOH). In 2,2,2,‐trifluoroethanol–H2O, the S values are much lower at about 0.1. Entropy of activation values are appreciably negative. Literature values for the specific rates of solvolysis of methanesulfonyl chloride have been extended to fluoroalcohol‐containing solvents (titrimetric method) and, at 45.0 °C, for an overall 43 solvents values are obtained (using NT and YC1 scales) of 1.20 for ? and of 0.52 for m (R = 0.969). It is proposed that both substrates solvolyze by an SN2 pathway. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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薛童  张日成  闫喜龙 《化学通报》2015,78(12):1162-1165
在有机合成反应中常使用甲基磺酰氯与醇反应,将羟基转化为易于离去的甲磺酸酯基。在近期的实验中,我们却发现N-甲基二乙醇胺同甲基磺酰氯反应生成的是羟基被氯取代的产物。我们设计了一系列实验推测生成氯取代产物的关键原因是在反应过程中生成了三元环的氮鎓离子过渡态,而形成这一过渡态必须满足的条件是:氮原子与羟基之间相隔两个碳原子,氮原子有足够的电子云密度,氮原子周围的空间位阻不能太大。  相似文献   
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甲基磺酰氯的合成党占青,康汝洪,武瑞涛,张兰平(石家庄师范专科学校化学系石家庄))(河北师范大化化学系石家庄050016)关键词甲基磺酰氯,合成,甲基异硫脲硫酸盐,氧化反应甲基磺酰氯是酯化、聚合的催化剂,染料、医药、农药等的重要化工原料。已报道的合成...  相似文献   
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Polysulfonylamines. CXV. Rubidium Di(methanesulfonyl)amide, 18-Crown-6, and Water as Building Blocks of a Three-Dimensional Hydrogen-Bond Network: Preparation and Crystal Structure of [Rb(18-crown-6)(H2O)2{(MeSO2)2N}] · H2O The title complex (orthorhombic, space group P212121, Z = 4, X-ray analysis at –130 °C) was obtained by co-crystallizing equimolar amounts of RbN(SO2Me)2 and 18-crown-6 from water/methanol (1/1). The crown ether displays effective D3d symmetry; the Rb ion is displaced by 99.5(1) pm from the mean plane of the macrocyclic oxygen atoms [Rb–O 290.2(3)–309.7(3) pm] and thus adopts a typical “sunrise coordination”. Two Rb–O contacts from water molecules [295.1(4) and 323.0(4) pm] and a Rb–O contact from the anion [292.0(4) pm], all situated on the opposite side from the crown ether, complete the coordination of the cation. Hydrogen bonding plays a major role in the crystal packing. The complex units, excluding the non-coordinating water molecules, are associated into strands by (H2O) catenation and water…anion hydrogen bonds. The non-coordinating water molecules, located between the parallel strands, cross-link each of them with four adjacent equivalents via water…anion bonds to generate a three-dimensional network.  相似文献   
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Polysulfonylamines. XCIX. The First Boron(III) Di(organosulfonyl)amides: A Novel B(OS)2N Six-Membered Ring and Two Aminoborane Structures with Long B–N Bonds Ph2B[N(SO2Me)2] ( 1 ) and the benzo-1,3,2-dioxaboroles C6H4O2BN(SO2R)2, where R = Ph ( 2 a ) or Me ( 2 b ), were prepared by treating the appropriate bromoboranes with Me3SiN(SO2Me)2 and/or AgN(SO2R)2. Their crystal and molecular structures were determined by low-temperature X-ray diffraction ( 1 : monoclinic, space group P21/n; 2 a : monoclinic, P21/c; 2 b : triclinic, P 1, structure marred by disorder of one MeSO2 group). The B atom of 1 features a distorted tetrahedral coordination formed by the ipso-C atoms of the Ph groups and two O atoms of the 1,5-chelating (MeSO2)2N7 anion (B–O 156.5, 157.7 pm). The resulting six-membered B(OS)2N ring adopts a boat conformation, B and N lying out of the plane of the other four atoms. In the chelate ligand, which is severely distorted from the common pseudo-C2 symmetry of the discrete anion, extremely long S–O(B) bonds (151.2, 151.7 pm) are compensated by short N–S bonds (156.1, 156.8 pm). Molecules 2 a and 2 b have aminoborane structures with trigonal-planar coordinations at B and N, unusually long B–N distances suggesting single bonds [ 2 a : 147.6(3), 2 b : 146.3(5) pm], and fairly short N–S bonds ( 2 a : av. 167.4, 2 b : av. 170.4 pm). In 2 a the O2B plane is twisted by 70.9° vs. the NS2 plane, whereas the O2B–NS2 moiety of 2 b is approximately coplanar (twist-angle ca. 9°).  相似文献   
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