摘要:

The35Cl nuclear quadrupole resonance frequencies of BCl3, two amine complexes, and five nitrile complexes of BCl3are reported for 77 °K. Two molecular orbital theories, BEEM-π and CNDO, are used to interpret the frequencies.The temperature dependences of the35Cl nuclear quadrupole resonance frequencies of B-trichloroborazole are reported.

ISSN:0008-4042    

DOI:10.1139/v70-115

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

With203Hg as a tracer, the volatility of Hg(NO3)2and HgCl2in the presence of HNO3, HCl, H2S, Na2S, NaHS, Na2S2O3, and NH3has been studied. The amounts of mercury varied between 1 and 50 μg and the other experimental conditions were those encountered in the preparation of radioactivity standards. We found that the losses of activity were large during the evaporation of solutions of Hg(NO3)2in HNO3, that they were nil during the evaporation of solutions of HgCl2in HCl, and that they were large again for the solid residues left after the evaporation of each one of these solutions. When using a solution of Hg(NO3)2in HNO3, we found it very difficult to eliminate completely the losses by a HgS precipitation; we stopped them completely only by addition of a large excess of sulfide ion as Na2S and NaHS or of Na2S2O3. The precipitation of HgS from a solution of HgCl2in HCl is much easier and stops the losses completely.The results can be explained by saying that the formation of the HgCl42−complex in a HCl medium greatly stabilizes the mercuric ion and renders it nonvolatile, whereas the formation of volatile Hg(NO3)2molecules is favored in a HNO3medium where no complex formation occurs.

ISSN:0008-4042    

DOI:10.1139/v70-116

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Methyltin trinitrate has been prepared by the reaction of dinitrogen pentoxide on methyltin trichloride in carbon tetrachloride, followed by sublimation in vacuo at 60 °C. Conductivities and ultraviolet spectra of methyltin trinitrate in several solvents are reported. Vibrational spectra indicate that the three nitrato groups are all bonded in the same bidentate manner and the reactivity of the compound towards aliphatic hydrocarbons and diethyl ether shows that the compound is chemically similar to tin(IV) nitrate. The vibrational spectrum of methyltin trinitrate is compared with those for trimethyltin nitrate, dimethyltin dinitrate, and tin(IV) nitrate. Nuclear magnetic resonance spectra have been determined for the series MenSn(NO3)4−n(n = 1,…, 4), and a comparison of the117Sn– and119Sn–proton coupling constants for the series has been made showing that the tin atom becomes more electron deficient and has more s character in its bonding orbital to carbon asndecreases. The pyridine adduct MeSn(NO3)3•2py has been prepared and the infrared spectrum of this compound indicates that the nitrate groups are unidentate.

ISSN:0008-4042    

DOI:10.1139/v70-117

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Wide-line nuclear magnetic resonance studies of methylammonium chloride, bromide, and iodide and their partially deuterated analogues show that second-moment and line-width transitions occur which can be interpreted as due to molecular reorientation about the C—N axes. In the bromide and iodide salts this motion persists below 77 °K.

ISSN:0008-4042    

DOI:10.1139/v70-118

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Experiments were made to determine the effect of conditions in chloride solution on the formation of gibbsite. It was found that the temperature of the systems and the chloride concentration in solution had a marked effect on the rate of all the reactions occurring. In all cases gibbsite was identified as the final product, except when the temperature was 10 °C and when the chloride concentration was about 0.6 N. When the temperature was 10 °C the reactions were very slow, and there was no reason to believe that gibbsite would not have been the final product if sufficient time had been allowed. In the system in which the chloride concentration was about 0.6 N, the final product was an aluminum hydroxychloride. In all systems the concentration of polynuclear hydroxyaluminum ions started at relatively low values, increased with time to a maximum, and then decreased, while with the solids the reverse was true. A mechanism for the formation of gibbsite is proposed.

ISSN:0008-4042    

DOI:10.1139/v70-119

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Ketone4reacted thermally with a series of terminal alkenes, forming unsaturated alcohols of type-1. The failure of4to react with internal or cyclic alkenes, with some alkenes at multiple ratios, or to more than a limited extent with the pendant vinyl groups of polybutadiene, suggests a high degree of steric inhibition in this reaction compared with hexafluoroacetone. Several allyl ethers formed tetrahydrofuran derivatives (type-2). 4-Allylanisole uniquely formed a type-1product thermally convertible to type-2. Type-2derivatives could also be obtained fromsym-tetrafluorodichloroacetone, but not from diethyl oxomalonate.

ISSN:0008-4042    

DOI:10.1139/v70-120

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Sulfurated sodium borohydride can reduce oximes to the corresponding amine with yields depending on the steric requirement of the oxime. Intermediate hydroxylamine can be obtained predominantly under appropriate experimental conditions. A reaction mechanism taking into account the availability of only one hydrogen for reduction on the hydride and the production of intermediate hydroxylamine is proposed.

ISSN:0008-4042    

DOI:10.1139/v70-121

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The mass spectra of several dimethylquinolines, labelled in the methyl group with deuterium, have been examined. The results are in agreement with the formation of ring-expanded molecular ions prior to fragmentation to the M—H and M—CH3ions. Two ring-expanded ions may form since there are two methyl groups which can participate in the ring expansion process. Ring expansion through a methyl group located on the benzenoid ring is favored over ring expansion through a methyl group on the pyridine ring.

ISSN:0008-4042    

DOI:10.1139/v70-122

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The mass spectra of some labelled methylquinolines have been studied. Randomization of all nine hydrogens in the molecule appears to precede hydrogen loss in the fragmentation of the monomethylquinolines and the formation of ring expanded intermediates is proposed to account for the randomization. Possible mechanisms for the ring expansion are considered.

ISSN:0008-4042    

DOI:10.1139/v70-123

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

A general analytical power-series solution of the Gibbs–Duhem equation in multicomponent systems of any number of components has been developed. The simplicity and usefulness of the solution is made possible through the choice of a special set of composition variables.

ISSN:0008-4042    

DOI:10.1139/v70-124

出版商:NRC Research Press    

年代:1970

数据来源: NRC