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121.
Luca Giannini Silvia Dovesi Euro Solari Carlo Floriani Angiola Chiesi-Villa Corrado Rizzoli 《Angewandte Chemie (International ed. in English)》1999,38(6):807-810
The chemically reversible reduction of [(Me)2W(calix)] to the diamagnetic [(Me)2W(calix)Na2] [Eq. (1)], without major changes in the connectivity of the molecule, illustrates the flexibility of the calixarene ligand and stresses its potential as a molecular functional model of heterogeneous oxo surfaces. 相似文献
122.
Jeanne Crassous Jos Rivera Nicolette S. Fender Lianhe Shu Luis Echegoyen Carlo Thilgen Andreas Herrmann Franois Diederich 《Angewandte Chemie (International ed. in English)》1999,38(11):1613-1617
The pure enantiomers of D 2 -C 84 as well as a third constitutional isomer of this higher fullerene were produced by a retro-Bingel reaction on the first organic derivatives of C84 (see scheme). These derivatives were synthesized by Bingel cyclopropenation of C84, separated, and unambiguously structurally characterized. 相似文献
123.
Vincenzo G. Albano Carlo Castellari Cristina Femoni M. Carmela Iapalucci Giuliano Longoni Magda Monari Stefano Zacchini 《Journal of Cluster Science》2001,12(1):75-87
The new Au8{Fe(CO)4}4(P^P)2 and Au6Cu2{Fe(CO)4}4(P^P)2 (P^P=dppm, dppe) neutral cluster compounds were isolated in good yields by condensation of the [Au3{Fe(CO)4}2(P^P)]- anions with Au(SEt2)Cl and CuCl, respectively, and have been characterized by IR, NMR and microanalyses. The molecular structures of Au8{Fe(CO)4}4(dppe)2 and Au6Cu2{Fe(CO)4}4(dppe)2 have been determined by X-ray diffraction studies. Both molecules adopt a stereogeometry of the heavy atoms consisting of a triangulated and corrugated ribbon twisted around the elongation direction. Contrary to the expectations the latter displays the two copper atoms in the sites of highest connectivity. This implies that site exchange between copper and gold occurs during the synthesis. 相似文献
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126.
Carlo Anchisi Luciana Corda Antonio Maccioni Gianni Podda 《Journal of heterocyclic chemistry》1982,19(1):141-144
The action of acyl halides on heterocyclic compounds of five-membered rings containing an O-M-O (M ? P, As, Sb) linkage is described. The reactions were either carried out in the presence of a solvent (benzene or toluene) or by direct heating of the reagent with the substrate. In the case of arsole, stibole and stannole derivatives, the cleavage of O-M bond and the formation of the respective mono- and diesters were always obtained, while with the phospholes, no cleavage of the compounds was observed. The products IIa-c (M = Sb) have been obtained in excellent yields starting from VIa-c and antimony trichloride. The structure of the compounds which were prepared was determined by analytical and spectroscopic methods and also by comparations with authentic samples where possible. 相似文献
127.
128.
Mario Di Braccio Giorgio Roma Gian Carlo Grossi Giovanni Ciarallo 《Journal of heterocyclic chemistry》1992,29(1):25-31
The reaction of 2-[(N-acyl, N-alkyl or phenyl)amino]-4H-pyrido[1,2-a]pyrimidin-4-ones 8a-g with the N,N-dimethylformamide/phosphorus oxychloride Vilsmeier reagent 1 (95°, 90 minutes) afforded 1-alkyl or phenyl-2H-dipyrido[1,2-a:2′,3′-d]pyrimidine-2,5(1H)?diones, 3-alkyl substituted or not, 10a-g . The starting compounds 8 were prepared by treating 2-amino-4H-pyrido[1,2-a]pyrimidin-4-ones N-alkyl substituted 7a,b or N-phenyl substituted 4 with excess anhydrides (130°, 7 hours) when the 2-(alkylamino) derivatives 7 were used in the reaction, compounds 8 were obtained along with very small amounts of 3-acyl-2-(alkylamino)-4H-pyrido[1,2-a]pyrimidin-4-ones 9 . 相似文献
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130.
Maura Pellei Carlo Santini Giancarlo Gioia Lobbia Franco Cantalamessa Cinzia Nasuti Mariacristina Di Prinzio Rosita Gabbianelli Giancarlo Falcioni 《应用有机金属化学》2005,19(5):583-589
New organotin(IV) derivatives containing the anionic ligands bis(3,5‐dimethylpyrazol‐1‐yl)dithioacetate [LCS2]− and bis(3,5‐dimethylpyrazol‐1‐yl)acetate [LCO2]− have been synthesized from reaction between (CH3)2SnCl2 and lithium salts of the ligands. Mononuclear complexes of the type {[LCX2](CH3)2SnCl} (X = S or O) have been obtained and fully characterized by elemental analyses and FT‐IR in the solid state and by NMR (1H, 13C and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry in solution. The acute toxicity of new organotin(IV) derivatives on rat was studied, comparing their effect with those of dimethyltin chloride (CH3)2SnCl2. The comparison of LD50 of organotin(IV) complexes and (CH3)2SnCl2 administered intraperitoneally, as a single dose, evaluated in vivo on rats, showed that toxicity decreases as follows: (CH3)2SnCl2 > LCO2 > LCS2. The effect of these organotin(IV) complexes on DNA was evaluated in vitro and in vivo on rats treated with different doses of these compounds (1/20 LD50 and 1/100 LD50). The lymphocyte DNA status was assessed by the comet assay, a rapid and sensitive single‐cell electrophoresis technique, used to detect primary DNA damage in individual cells. After 36 h from the start of treatment the two new organotin(IV) derivatives induced a significant rise in comet assay parameters, indicating an increasing presence of damaged DNA. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献