Prototropy in HPCC triad of alkyl(α-ethoxyethenyl)phosphines
作者:Yuri A. Veits、Natalia B. Karlstedt、Irina P. Beletskaya
DOI:10.1016/0040-4039(95)00674-2
日期:1995.6
Palladium-catalyzed cross-coupling of alkyl(trimethylsilyl)phosphines with (α-bromoethenyl)ethyl ethers leads to secondary alkyl(α-ethoxyethenyl)phosphines. The latter present first example of the compounds with reversible intramolecular [1,3]-shift of hydrogen in PCCtriad.
Nickel- and palladium-catalyzed cross-coupling as a route to 1- and 2-alkoxy- or dialkylaminovinylphosphonates
作者:Marina A. Kazankova、Inna G. Trostyanskaya、Serghey V. Lutsenko、Irina P. Beletskaya
DOI:10.1016/s0040-4039(98)02358-2
日期:1999.1
1- and 2-alkoxy- or dialkylaminovinylphosphonates were synthesized using reactions of the corresponding vinylhalides with di- and triethylphosphites in the presence of catalytic amounts of Ni salts and Pd complexes. The best way for synthesis of I-alkoxy or dialkylaminoderivatives is the Pd-catalyzed cross-coupling reaction with (EtO)(2)POH and the best way for 2-alkoxy- or dialkylaminovinylphosphonates is the Arbuzov reaction with (EtO)(3)P catalyzed by Ni salts. (C) 1998 Elsevier Science Ltd. All rights reserved.
Kazankova; Trostyanskaya; Lutsenko, Russian Journal of Organic Chemistry, 1999, vol. 35, # 9, p. 1273 - 1277
作者:P. C. BUCHANAN、D. J. LINDSTROM、D. W. MITTLEFEHLDT、C. KOEBERL、W. U. REMOLD
DOI:10.1111/j.1945-5100.2000.tb01519.x
日期:2000.11
Abstract— The polymict eucrite Macibini is a fragmental breccia, predominantly composed of eucritic materials with minor proportions (maximum 2 vol%) of diogenitic material. Hence, it is intermediate between the Yamato‐74159‐type polymict eucrites, which contain negligible amounts of magnesian orthopyroxene, and the howardites. The present study provides mineralogical and bulk compositional data for the meteorite breccia and for six clasts. These clasts include both volcanic and igneous rocks and a variety of impact‐generated rocks. A broad range of degrees of postcrystallization metamorphism affected these materials before the final aggregation of the breccia.Clast A is a fragment of unequilibrated eucrite with subophitic texture. The edges of the zoned pyroxenes in this clast are composed of a host of Fe‐rich augite containing vermicules (blebs) and lamellae composed of a mixture of Fe‐rich olivine and silica. Similar features occur as fragments in lunar breccias and are attributed by some workers to the breakdown of pyroxferroite, an Fe‐rich pyroxenoid. However, textures and compositions of these augite‐olivine‐silica intergrowths in clast A suggest that, in this case, they are the result of decomposition in a series of steps of Fe‐rich subcalcic augite.Among the fragments of impact‐generated material in Macibini is clast 2, an earlier‐formed clastic breccia that was lithified before being broken apart and included in the meteorite breccia. Clast 3 is an impact‐melt breccia that is composed of rock and mineral fragments in a devitrified groundmass. Clast C is also an impact‐melt breccia that has a coarser‐grained, hornfelsic groundmass that resulted from extensive metamorphism after formation.