摘要:

Complexes of thiomorpholin-3-one, thiomorpholin-3-thione, thiazolidine-2-thione, and thiazolidine-2-selenone with CrX3•nH2O (X = Cl, Br, I) were prepared and characterized. On the basis of vibrational (conventional and far infrared) and electronic spectroscopy, magnetism and conductivity measurements, the structures of these complexes were identified. The bonding occurs through the oxygen in the complexes of thiomorpholin-3-one and through the nitrogen in all the remaining complexes. The complexes crL3x3involve unidentate ligands, are neutral, monomeric, and hexacoordinate. Spectroscopic parameters for the complexes have been calculated and compared with similar chromophores containing CrN3X3, CrO3X3, and CrS3X3chromophores.

ISSN:0008-4042    

DOI:10.1139/v74-413

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Resonance Raman spectra of dilute aqueous solutions of Cu-tetrapyridinoporphyrazine have been obtained using a tunable dye and Ar+lasers. Six bands in the spectra have anomalous depolarization ratios. This is the first observation of anomalous polarization in a molecule of C4hpoint group symmetry. Intensities and depolarization ratio, ρ1, of the observed bands are measured as a function of the wavelength of the exciting radiation. Bands are assigned to different symmetry species on the basis of the dispersion of their ρlvalues.

ISSN:0008-4042    

DOI:10.1139/v74-414

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Isomerizations of 1-olefins were carried out with dihalogenobis(nitrile)palladium(II). The activity of palladium complexes decreased in the orderThe ratio ofcis-2-olefin totrans-2-olefin, which exceeded the thermal equilibrium ratio, decreased in the order CI > Br > I, while nitriles did not influence this ratio. The reactivity of olefins decreased in the orderThe isomerization of 1-butene was accelerated by the presence of other olefins. Addition of lithium borohydride also accelerated the isomerization of olefins. The nature of active species and the effects of ligands on activity are discussed.

ISSN:0008-4042    

DOI:10.1139/v74-415

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

A study of low resolution mass spectra of 1,2,4-triazoles shows that fragmentations ofC-amino-l,2,4-triazole nuclei are analogous to the three fragmentation modes reported for pyrrole. The extent to which these fragmentations account for the peaks in the mass spectra depends on the substituents of the 1,2,4-triazoIes. Mass spectra of C-azido-l,2,4-triazoles cannot be interpreted by the three modes found for pyrrole. Without exception, their mass spectra contain a base peak which is shown, with the aid of deuterium labeling, to represent an ion formed by the loss of four nitrogen atoms plus the substituent on the endocyclic nitrogen atom.

ISSN:0008-4042    

DOI:10.1139/v74-416

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Trimethylamine adducts of the boron trihalides, Me3N•BX3are shown to react in solution with free boron trihalides BY3to yield mixed halide adducts such as Me3N•BX2Y. Isotope labelling shows that the B—N bond remains intact and that the reaction proceeds in either direction,i.e. either X or Y may be the heavier halogen. A bridged transition state involving five-coordinate boron is postulated. Only in the case of Me3N•BI3is an ionic predissociation of a B—X bond indicated by reaction with ionic species. Two adducts do not react in solution without the presence of excess Lewis acid, again indicative of a lack of predissociation. In the gas phase two adducts will scramble their halogens even in the absence of excess acid but these reactions occur via B—N bond cleavage.

ISSN:0008-4042    

DOI:10.1139/v74-417

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The catecholamine analogs (±)-1-(3,4-dimethoxyphenyl)-2-alanine (1), β-(3,4-dimethoxyphenyl)ethylamine (2), (±)-1-(3,4-dimethoxyphenyl)-2-amino propane (3), (±)-erythro,threo-α-aminomethyl-3,4-dimethoxybenzyl alcohol (4), and (±)-erythro,threo-α-methylaminomethyl-3,4-dimethoxybenzyl alcohol (5) have been synthesized and optimized yields are reported. The availability of certain carbon-14 compounds has dictated logical starting points in the synthesis of14C-tagged analogs. These syntheses were designed for metabolic and disposition work in connection with a pilot project concerned with the aetiology of schizophrenia with particular reference to the Osmond–Smythies – Harley-Mason hypothesis (2) of 1952.

ISSN:0008-4042    

DOI:10.1139/v74-418

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Titanium tetrachloride reacts rapidly with trichloro-, tribromo- and methyldichlorophosphine in the presence oft-butyl chloride to give compounds containing a phosphonium cation R1R2PX2+(R1 = t-butyl, R2 = chloride, bromide, or methyl, X = chloride or bromide) and the principal metal-containing anion, Ti2Cl9−. For tribromophosphine andt-butyl chloride a stoichiometric product, [ButPBr3][Ti2Cl9] was obtained which was characterized using vibrational spectroscopy. The other reactions gave non-stoichiometric materials, the sublimates of which may contain higher polymeric anions whilst the residues contained TiCl5−along with the parent dimeric anion.Zirconium tetrachloride and titanium tetrabromide reacted in a similar way to give the new ions Zr2Cl9−and Ti2Br9−in stoichiometric reactions.

ISSN:0008-4042    

DOI:10.1139/v74-419

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Rate constants for the quenching of singlet oxygen by a series of substitutedN,N-dimethylanilines were obtained by a direct method employing a dye-laser. The Hammett ρ value obtained from the data (−1.71) suggests that a (partial) charge-transfer complex may be responsible for the quenching action. This rate data was combined with that obtained for the total quenching action on the sensitized photooxidation of 1,3-diphenylfuran. The quenching action on the photooxidation reaction is due to both the quenching of singlet oxygen and the quenching of the triplet state of the sensitizer (rose bengal or methylene blue). The combination of the data from each series of experiments resulted in rate constants of quenching of the triplet states of the sensitizers. A number of theN,N-dimethylanilines quenched the triplet states at the diffusion limit. Hammett ρ values (−1.86 for rose bengal and −4.19 for methylene blue) indicate that charge-transfer intermediates are probably responsible for the quenching action. This was confirmed by the observation of a transient intermediate assigned to the charge-transfer radical of methylene blue. The technique used here represents a novel approach to the investigation of triplet states.

ISSN:0008-4042    

DOI:10.1139/v74-420

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The addition of enynic phosphonatesto alcohols in the presence of boron trifluoride, leads to γ,δ-ethylenic β-ketophosphonates.Yields of 70% have been obtained. WhetherZorEenynic derivates are starting materials theEketophosphonate is obtained in both cases. The dipole moments of both families of compounds have been measured.

ISSN:0008-4042    

DOI:10.1139/v74-421

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The formation and the stability of some arylsilyl adducts of phenyltert-butyl nitrone were studied in a photochemical system using di-tert-butyl peroxide as solvent. The β-proton splittings of all the arylsilyl adducts, ranging from 5.6 to 8.3 G, are relatively larger than their carbon analogs, which are usually less than 4 G. The arylsilyl adducts are found to decompose in di-tert-butyl peroxide solvent by a first-order kinetics. The activation energy involved in the decomposition of a series of arylsilyl adducts varies from about 14 to about 9 kcal/mol, as the size of the silyl group increases. In all cases, very low values of theAfactors (between 106and 1010) were observed.

ISSN:0008-4042    

DOI:10.1139/v74-422

出版商:NRC Research Press    

年代:1974

数据来源: NRC