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51.
Aldehydes and ketones containing no α-hydrogen atoms yield the corresponding dialkylidene sulfamides both by reacting with sulfamide in presence of a proton acid or of SOCl2 and by reacting with bis(trichlorphosphazo)-sulfone. The dialkylidene sulfamides of ketones also were obtained by treating ketone imines with sulfamide. Chloral did not react with sulfamide in this way but yielded 3,7-bis-(trichloromethyl)-perhydro-1,5,2,4,6,8-dithiatetrazocine-1,1,5,5-tetroxide.  相似文献   
52.
The title compounds7 are formed in a general reaction by heating β-isothiocyanoketones3 with primary amines in inert solvents, or by thermal elimination of water from tetrahydro-6-hydroxy-6-methyl-2(1H)-pyrimidinethiones5, also in inert solvents. The 1-alkyl compounds can also be prepared under similar conditions from α,β-unsaturated ketones by reaction with alkylammonium rhodanides. The NMR-spectra show that the 1-substituted dihydro-6-methyl-2(1H)-pyrimidinethiones are in tautomeric equilibrium with the tetrahydro-6-methylene-2(1H)-pyrimidinethiones13. The reactivity of 1-alkyl and 1-aryldihydro-6-methyl-2(1H)-pyrimidinethiones is similar to that of dihydro-4,4,6-trimethyl-2(1H)-pyrimidinethione7 j, although their ring stability is certainly less.  相似文献   
53.
The infrared and laser-Raman spectra of crystalline Mg3(VO4)2 are reported and a factor group analysis for the full lattice is presented to support the discussion. The 1,000 to 600 cm?1 region of the spectrum is essentially related to internal (stretching) modes of the greatly distorted VO4 tetrahedra, whereas the bands in the low frequency region must be assigned to complex vibrations originating in the interaction of the bending vibrations of the tetrahedral groups with the external modes.  相似文献   
54.
The reaction of aminofluorsilanes of the type (R=H,F) (Me 3Si)2N?SiF2R with two moles of ammonia, or of a mono- or dialkylamine, yields the corresponding amino-compounds, e.g. (Me 3Si)2N?Si(F)R?NH2, (Me 3Si)2N?Si(F)R?NHR′ and (Me 3Si)2N?Si(F)R?NR2′ (R′=Me, Et). Analogous products are obtained by reaction of the aminofluorosilanes with lithium salts of amines with bulky organic substituents in a 1 : 1 molar ratio. Alkoxy- and aryloxyaminofluorosilanes are prepared by the reaction of sodium alcoholates and sodium phenolate with (Me 3Si)2N?Si(F2)R (R=H, C2H3, C2H5, C6H5). The i.r.-, mass-,1H- and19F-NMR spectra of the above compounds are reported.  相似文献   
55.
Tribromomanganese(II) acid has been prepared for the first time and will be described. A complex of the acid with pyridine was obtained and its UV, visible, IR and1H-NMR spectra will be reported.  相似文献   
56.
57.
The oxidation kinetics of cycloheptanone by chloramine-T in alkaline media has been investigated. A mechanism involving the formation of an intermediate by the interaction between the enolic anion of cycloheptanone and chloramine-T in a slow step followed by its interaction with another molecule of chloramine-T in a fast step leading to products has been proposed. The scheme satisfactorily accords with the observed stoichiometry, negligible influence of ionic strength and a positive dielectric effect. Various rate parameters have been computed and 1.2-cycloheptanedione identified as the end product.With 2 Figures  相似文献   
58.
The phase diagrams of the systems CsN3/Zn(N3)2 and KN3/Zn(N3)2 have been obtained employing the microscopic technique ofL. Kofler andA. Kofler. Within the system CsN3/Zn(N3)2 three eutectics at 148°C, 142°C, and 210°C were found. Besides Cs2Zn(N3)4, melting incongruently in the interval 153°C to 170°C, there exist two further compounds of the most probable composition Cs3Zn2(N3)7 and CsZn2(N3)5, melting congruently at 170°C and 210°C, resp. In the system KN3/Zn(N3)2 there exist two eutectics at 203°C and 172°C and two compounds, one of them, i.e. K2Zn(N3)4, melting congruently at 206°C, the other one, with composition KZn3(N3)7 or KZn4(N3)9, melting incongruently at 210°C.

Mit 8 Abbildungen

Herrn Professor Dr.Heribert Grubitsch zum 70. Geburtstag gewidmet.  相似文献   
59.
At photolysis (253.7 nm) of monophenylphosphate (10?3 m) in O2-free neutral aqueous solution were determined: orthophosphate (Φ=0.006), phenol (Φ=0.0029), besides of small amounts of phosphorous acid, benzene, 2.2′-dihydroxybiphenyl and traces of 2.4′- and 4.4′-dihydroxybiphenyl. The yield of the main products is smaller at pH 2 and 12. Polymers were formed at u.v.-doses >2·1019 hv/ml. The electron yield determined by means of N2O increases from Φ (N2)= Φ(e aq ? )=0.012 to 0.019 changing the ester concentration from 0.001 to 0.1m. Φ (N2)-value rises by addition of methanol or increasing pH. As electron ejecting state an excited complex is postulated. The effective ionization potential of phenylphosphate in aqueous solution is ≦4.9 e.v.  相似文献   
60.
The synthesis of 5-(o-trifluoromethylphenyl)-1H-thieno-[3,4-e]1,4-diazepin-2(3H)-one (7) and its nitration and chlorination in pos. 8 are described.  相似文献   
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