Tetrameric compounds

Fig. 10. Formation of bicyclic products in the aminolysis reaction of the tetrameric compounds.

However, when X = Cl a dimer [8] is formed which contains a four-membered (Li-0>2 ring system. By crystallizing the lithiated derivative of di-tert-butylfluorosilanol it was possible to isolate a stable aquo-complex of the tetrameric compound as the first hydrolysis product [9]. 

Phosphonitrilic halides (continued) primary amines and, 1 360-362 secondary amines and, 1 350-362 tertiaiy amines and, 1 362-363 structural theory further aspects of, 1 375 structure, 1 365-366 high polymer and, 1 372 medium polymers and, 1 368-372 spectroscopic data and, 1 369-372 structural theory and, 1 372-375 tetrameric compounds and, 1 367-368 trimeric compounds and, 1 366-367 Phosphonium cations, 9 243-250 halogenated, 9 243-249 salts... 

FIGURE 5. Cubane structure of the tetrameric compounds RMgOR. The tetramers are thermodynamically favoured when the alkyl groups are small and the solvent is only weakly co-ordinating... 

Fe20(0Ac)2Cl2(bipy)2 successfully hydroxylates C6, C3, and C2 alkanes when tert-butyl hydrogen peroxide (TBHP) is used as the oxygen donor ([5] [TBHP]-.[substrate] = 1 150 1100) the observed reactivity is C6 > C3 > C2 (Table IV). This work represents the first report of the oxidation of a small molecular weight alkane (ethane) by a characterized iron model compound. Reactions of this complex with Zn dust and acetic acid under 1 atm of dioxygen with cyclohexane gave rise to only cyclohexanone (turnover number 2.5). The parent tetrameric compound, 6, was reported to be a more efficient catalyst. 

This coordinated structure, which was entirely novel in 1936, is not limited to copper(I) iodide derivatives. Silver(I) iodide forms similar tetrameric compounds with tertiary phosphines and arsines, and since tetrakis(monoiodo-tri-n-propylarsinesilver), [ (C3H 7) 3As,Agl]4, is strictly isomorphous with tetrakis (monoiodo-triethylarsinecopper), the two series have identical structures Hi). 

Pyrolysis of tri-, tetra-, and penta-chlorobenzenes affords mixtures of chlorinated dibenzofurans and dibenzo-p-dioxins, " and chlorinated diphenyl ethers cyclize in the presence of palladium acetate to polychloro-dibenzofurans/ The action of malononitrile on tetrahydroxy-p-benzoquinone leads to the benzo-difuran (79), contrary to a previous report/ The acid-catalysed condensation of quinones with phenols has been studied p-benzoquinone and resorcinol, for example, afford compound (80)/ Naphtho[2,3- >]furan-4,9-diones (81 R = Me or Ph R = Ac, Bz, C02Et, or CN) are obtained from 2,3-dichloronaphtho-1,4-quinone and compounds R COCHaR in DMF that contains potassium fluoride/ The action of mineral acids on p-benzoquinone produces a mixture of complex benzofurans, which includes (82) and (83)/ Bases convert the ben-zofuranone (84) into the tetrameric compound (85), contrary to an earlier... 

Unsymmetrical amidinate ligands with an N-H functionality have likewise been shown to be suitable ligands for silicon coordination centers [4, 7]. In the case of germanium(ii), a tetrameric compound 4 has been obtained according to Eq. 3 [4]. 

Hexamethylbenzene forms a tetrameric compound [( / -C6Me6)SnCl(AlCl4)]4 in which secondary Sn- Cl bonds hold the self-organized structure together it has... 

When we reinvestigated the base-induced reaction of 1-naphthol with formaldehyde we isolated and identified three isomeric tetrameric compounds [2] which we named calix[4]naphthalenes by analogy with the calix[4]arenes and cal-ix[4]resorcinarenes. However, unlike the latter which are derived fromp-substituted phenols and resorcinol respectively, several different isomers can theoretically exist for the calix[4]naphthalenes. Additionally, the conformations that are possible for some of these isomers are further complicated due to the dissymmetry that is introduced by the naphthalene rings. In this contribution we will describe some properties of this new class of compounds. 

Red or white phosphorus, as well as arsenic and antimony, can be used to reduce zirconium(IV) complexes. The reduction of the hydride complex of zirconium(IV), [ZrH2Cp2l, was carried out in toluene at room temperature and the tetrameric compound, (ZrCp2)4, was obtained. 

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