116-17-6Relevant articles and documents
Nucleophilic and acid catalysis in phosphoramidite alcoholysis
Nurminen,Mattinen,Loennberg
, p. 2159 - 2165 (2001)
Numerous triflates, mesylates, chlorides, trifluoroacetates and tetrazolides of trialkylammonium, pyridinium and azolium ions have been studied as activators for the reaction of N,N,O,O′-tetraisopropylphosphoramidite with propan-2-ol in acetonitrile. The progress of the reactions was followed by 31P NMR spectroscopy, and the pKa values of the activators were determined by a13C NMR spectroscopic method based on competing simultaneous protonation of two bases. The salts promoted the reaction both as acids and nucleophiles, the acidity playing a more important role than the nucleophilicity. The Bronsted α value for the general acid catalysis was observed to range from 0.6 to 0.9 and the βnucl value to be 0.2 (pKa of the conjugate acid used as the measure of nucleophilicity). Mixtures of neutral azoles or pyridines and weakly acidic ammonium salts were also shown to be useful activators that allow the acidity and nucleophilicity to be tuned independently of each other.
Mechanisms of the Photoreactions of Cp2Fe2(CO)4 with Phosphines and Chlorocarbons
Tyler, David R.,Schmidt, Maryke A.,Gray, Harry B.
, p. 6018 - 6021 (1983)
Irradiation (λ>500 nm) of Cp2Fe2(CO)4 (Cp = η5-C5H5) in the presence of PR3 (R = Ph, O-i-Pr) in cyclohexane solution at room temperature yields a single product, Cp2Fe2(CO)3(PR3).The reaction with PPh3 (366 nm) is inhibited by excess CO.A reaction intermediate was trapped by irradiating Cp2Fe2(CO)4 in the presence of P(O-i-Pr)3 at -78 deg C in ethyl chloride or THF solution.The infrared spectrum of the intermediate has ν(CO) = 1720 cm-1, and its electronic spectrum does not exhibit a ? ->?* band.The evidence suggests that the intermediate is Cp(CO)2Fe-CO-Fe(CO)(P(O-i-Pr)3)Cp, a molecule in which a single CO bridges the Fe atoms and in which there were no direct Fe-Fe bond.The mechanism of the photoreaction of PR3 with Cp2Fe2(CO)4 is proposed to involve formation of the CO-bridged intermediate Cp2Fe2(CO)4(PR3), followed by loss of CO to give the product Cp2Fe2(CO)3(PR3).The 366-nm photoreaction of Cp2Fe2(CO)4 with CCl4 or CHCl3 to give CpFe(CO)2Cl occurs mainly by a CpFe(CO)2 radical pathway, because the chlorine atom abstraction is not inhibited by 6 atm of CO.
ACYCLIC NUCLEOSIDE PHOSPHONATE DERIVATIVES AND MEDICINE USES THEREOF
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Page/Page column 12, (2012/11/06)
An acyclic nucleoside phosphonate derivative and medicine use thereof are provided. In detail, an acyclic nucleoside phosphonate derivative shown in formula I is provided, which has potent antiviral activity (such as hepatitis B virus activity) and less cytotoxicity, and pharmaceutically-acceptable salts, isomers, hydrates or solvates thereof, where, R1 is selected from H or methyl; each R2 is independently selected from -R3 or -OR3; and each R3 is independently selected from C1-C8 alkyl or C3-C8 cycloalkyl. A preparation method of the compounds shown in formula I, a pharmaceutical composition containing the compounds, and a medical application thereof are also provided. The acyclic nucleoside phosphonate derivative is effective for antivirus, such as hepatitis B virus, and is good in vivo behavior attributes.
Syntheses und NMR-Spektren phosphororganischer Antioxidantien und verwandter Verbindungen
Koenig, T.,Habicher, W.D.,Haehner, U.,Pionteck, J.,Rueger, C.,Schwetlick, K.
, p. 333 - 349 (2007/10/02)
The syntheses of various aliphatic, aromatic, sterically hindered, and cyclic organophosphorus compounds (phosphorous acid esters, esters chlorides and ester amides, hydrogen phosphites, phosphinates and phosphates) are reported, and general procedures for preparation are given.The compounds synthesized were investigated by means of 31P-, 1H- and 13C-n.m.r. spectroscopy, and the chemical shifts measured are listed.
