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A.R. Manning Gerald McNally Reg Davis Christopher C. Rowland 《Journal of organometallic chemistry》1983,259(2):C15-C16
Depending on the substrate and the reaction conditions, SO2Cl2 is a useful reagent which brings about either chlorination or the formation of cationic species on reaction with transition metal carbonyl complexes. 相似文献
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Syntheses of 5-isopropyl-1,3-cyclohexadiene and syn-5-isopropyl-2,3-dioxabicyclo[2.2.2]octane, by routes that would allow completely diastereoselective introduction of deuterium labels, are described. The reaction of the isopropyl cyclohexadiene with singlet oxygen is shown to give an endoperoxide that is derived by preferential attack on the more sterically hindered face of the diene. A possible mechanistic explanation of this result is that the attack from the less hindered face leads to "ene" reaction rather than endoperoxide formation. However, this mechanism would require that the "ene" reaction and cycloaddition proceed via a common intermediate-presumably a perepoxide. 相似文献
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The addition of R3SiCl to B(OTf)3 gives “supersilylating agents” formulated as R3SiB(OTf)3Cl. The catalytic properties of these species are similar to those of the previously-described (but less accessible) R3SiB(OTf)4. 相似文献
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J. M. Davis 《Chromatographia》1996,42(7-8):367-377
Summary The application of statistical models of overlap (SMOs) to saturated separations is made possible by theory that addresses variable peak amplitudes. These amplitudes cause peak widths to vary, and this variation can be modeled by a random variable whose effect on the probability of overlap is expressed by a convolution integral. Modified probabilities of overlap are derived for both homogeneous and nonhomogeneous one-dimensional separations, and the new probabilities are compared to results determined from published computer simulations. The new theory can describe overlap at saturations that are 3 to 4 times larger than before. Previously reported experimental chromatograms are reinterpreted to show the capabilities of theory. The theoretical extension is an important step towards making SMOs into practical tools for screening analytical separations. 相似文献
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First field free region metastable fragmentations of (η6-PhCH3)Cr(CO)3 have been examined by means of the linked scan technique. The molecular ion is shown to fragment exclusively by single and multiple CO loss. The ion [C7H8Cr(CO)2]+? also fragments directly to [C7H8Cr]+?. 相似文献