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1.
A new reaction of organolithium compounds with phosphonium salts is described; reaction of t-butyllithium with dibenzylaminophosphonium or tetraphenylphosphonium bromides takes place through addition of the t-butyl group on a benzene ring at the position para to the phosphorus atom, the ylid formed reacts in a characteristic Wittig reaction with p-tolylaldehyde.  相似文献   
2.
Reaction of carboxamides with Cu2O in the presence of t-butyl isocyanide gave new chelated copper(I) complexes, which probably are formed by the insertion of t-butyl isocyanide into the coppernitrogen bond of copper(I) amide isonitrile complexes, which were initially produced from the carboxamides and Cu2Ot-butyl isocyanide complex. The same chelated copper(I) complexes were prepared more readily by the reaction of the corresponding N-trimethylsilyl-carboxamides with Cu2Ot-butyl isocyanide complex. Reactions of the copper(I) complexes thus obtained with alkylating agents, such as alkyl halides, alkyl tosylates and triethyloxonium tetrafluoroborate, also were described.  相似文献   
3.
A computer algorithm is presented for the simulation of the effect of molecular tumbling on ESR spectra, and is applied to simulation of the conventional ESR signal (the absorption signal detected at the first harmonic of the modulation frequency and in-phase with the modulation frequency, in the limit of low microwave and modulation power) of axially symmetric 14N-nitroxide spin labels. The algorithm is extremely fast and is economical in terms of computer memory requirements.  相似文献   
4.
All the fundamental frequencies observed in IR and Raman spectra have been assigned to the normal modes of the molecule (C3H5)4Pb (C3H5 = cyclopropyl). The calculated force field is compared to that of (C3H5)2Hg and the Cmetal stretching force constants are discussed along with those of Me4Pb and Me2Hg; The similarity of the spectra of cyclopropyllead and cyclopropyl-mercury proves that the vibrations of cyclopropyl structural units are isolated in both molecules.  相似文献   
5.
Ru(C6Me6)(C2H4)2 reacts with Rh(C5Me5)(CO)2 to give the known dinuclear complex [Rh(C5Me5)(CO)]2 and the new heteronuclear cluster complex {[Rh(C5Me5)]3[Ru(CO)3](μ3-CO)2} which has been fully characterized by a single crystal X-ray diffraction study.  相似文献   
6.
The various expressions considered in Part I for the transition moment matrix elements of fundamental and first two overtones are applied to carbon monoxide. The coefficients aij in the expressions Rio = Σaijpj (where Rio is the transition moment integral for the O → i vibrational transition and pj is the dipole moment derivative ?jP/?XXXj, XXX = (rre)/re, re is equilibrium bond distance) are reported for i,j = 1, 2, 3. It is found that these coefficients do not vary by more than 5% when compared for the same i,j values in various expressions irrespective of the most exhaustive treatments used in deriving the original expressions. On the basis of the values of the coefficients obtained for CO, generalisations have been suggested on the effects of inclusion of mechanical and electrical anharmonicity to the intensities of fundamental and first two overtones. It is generally observed that the contribution of p'1, is about 100 fold more than the contribution of p'2, for R10. On the other hand the contributions of p'1, and p, for R20 and R30 are of nearly equal magnitude but opposite in sign. The contribution of p'1 to R10 is much higher than its contribution to R20 and R20. The various observations lead us to conclude that, whereas the effect of inclusion of mechanical anharmonicity on the intensity of the fundamental band is negligible, this effect is almost comparable to the effect of inclusion of electrical anharmonicity for the first two overtones. Simple forms of the aij expressions are applied to HC1 and OH to demonstrate the effect of variation of molecular constants on the aij values. On the basis of the observed trend in the values of these coefficients for CO, HCl and OH general remarks on the effects of hydrogen bonding on IR band intensities are given.  相似文献   
7.
The defense secretions of termite soldiers in the genera Amitermes, Noditermes, and Prorhinotermes contain sesqueterpene hydrocarbons, alcohols and ethers. Three new eudesmanes possessing the hitherto unknown 5β, 7β, 10β configuration were identified from Amitermesexcellens.  相似文献   
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9.
The preparation and properties of the complexes [M(π-C5H5){HC(NR)2}CO)2] (M = Mo, W; R = aryl or alkyl) are reported. The complex [Mo(π-C5H5){HC(N-p-tolyl)2}(CO)2] could be prepared by (a) reaction of MoCp(CO)3Cl with M′{HC(N-p-tolyl)2} (M′ = K, Ag or Cu); (b) irradiation of MoCp(CO)3Cl with HC(HN-p-tolyl)N-p-tolyl); and (c) reaction of [MoCp(CO)3]2 with M′{HC(N-p-tolyl)2} (M′ = Ag or Cu). The several routes to this complex give indications of the mechanisms of formation. The structure of these complexes and the bonding nature of the metal with the formamidino group is discussed on basis of the 1H and 13C NMR and IR spectra.Reaction of N,N′-dimethyl formamidine with MCp(CO)3Cl gave the complex [M(π-C5H5){HC(NMe)N(CO)Me}(CO)2], containing a carbonyl inserted between the metal and the formamidino group. Irradiation of this carbamoyl complex caused decarbonylation, yielding the complex [M(π-C5H5){HC(NMe)2}CO)2].  相似文献   
10.
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