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1.
By the reaction of FSO2N?PCl3 with perfluorpropionic acid FSO2NHC(O)C2F5 is formed, which yields FSO2N?C(Cl)? C2F5 (I) with PCl5. The chlorine atom in (I) could be replaced by the substituents NH2 (II) and N(C2H5)2 (III). FSO2N?C(Cl)? CF3 reacts with AgOCN, AgSCN, unhydrous HF and 2,3-dimethylbutadiene. FSO2N(CH3)? C(O)F reacts with elemental fluorine under exchange of a proton against a fluorine atom to give FSO2N(CH2F)? C(O)F, which liberates at room temperature COF2 and trimerises to form 1,3,5-Tris-fluorosulfonyl-s-triazine (VIII). The amides FSO2N?C(CH3)NH2 and FSO2N?C(CF3)NH2 react with SF4 in the presence of NaF to yield the iminosulfur difluorides FSO2N?C(CH3)? NSF2 (IX) and FSO2N?C(CF3)? NSF2 (X) 相似文献
2.
Ulrich Siemeling Thomas Türk Udo Vorfeld Heinrich Fink 《Monatshefte für Chemie / Chemical Monthly》2003,134(3):419-423
Summary. Chemoselective reduction of 1-nitro-2-(2-nitro-2-methylpropyl)-benzene to 2,2′-di-(2-nitro-2-methylpropyl)-azoxybenzene was
achieved with sodium borohydride in methanol in the presence of substoichiometric amounts of bismuth, whereas reduction with
zinc in hydrochloric acid gave a mixture of the latter, 1-amino-2-(2-amino-2-methylpropyl)-benzene, and 3,3-dimethyl-3,4-dihydrocinnoline,
and showed poor reproducibility. The crystal structure of the azoxybenzene was determined by single-crystal X-ray diffraction.
Corresponding author. E-mail: siemeling@uni-kassel.de
Received August 26, 2002; accepted September 2, 2002 相似文献
3.
Cline Schneider Frdric Doucet Stanislav Strekopytov Christopher Exley 《Polyhedron》2004,23(18):3185-3191
Hydroxyaluminosilicates (HAS) are critical secondary mineral phases in the biogeochemical cycle of aluminium. They are formed from the reaction of silicic acid (Si(OH)4) with an aluminium hydroxide template and act as a geochemical control of the biological availability of Al. There are two main forms of HAS which we have called HASA and HASB and which of these will predominate will depend upon the Si(OH)4 to Al ratio in any one environment. In all but the most heavily weathered environments or those undergoing a progressive acidification Si(OH)4 will be present in significant excess to Al and HASB will be the dominant secondary mineral phase. We have tried to determine the solubility of HASB(s) so that its contribution to Al solubility control might be compared with other secondary minerals such as Al(OH)3(gibbsite). In preliminary experiments, the dissolution of HASB(s) was found to be non-congruent with almost no Al being released during 18 months ageing. We then demonstrated that HASB(s) was significantly less soluble than Al(OH)3(s) prepared under identical experimental conditions. We have used this information to describe a solubility expression for HASB(s) at a predefined quasi-equibrium and to calculate a solubility constant.
K*Al2Si2O5(OH)4=[Al2O4+][SiO2]2[OH-]4