摘要:

Metal complexes of the tetradentate ligand bis(diacetyl-monoximeimino)propane 1,3 = [(DOH)2pn] are interesting in several respects. They are representatives of molecular systems containing very short hydrogen bonds; moreover, the organo-cobalt derivatives were reported as first examples of stable water-soluble compounds besides Vitamin B12coenzyme and alkylcobalamines1. From this point of view they were extensively investigated as models of Vitamin B122. However, vibrational data concerning these complexes are rather scarce: at our knowledge only a limited assignment was proposed by UHLIG and FRIEDRICH3for some Ni derivatives.

ISSN:0038-7010    

DOI:10.1080/00387017708065031

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

XY4Z molecules or ions with a square-pyramid structure (C4v) are relatively rare. This explains the infrequency of investigations of their vibrational spectra, with analysis in normal coordinates and computation of the mean-square amplitudes of vibration.

ISSN:0038-7010    

DOI:10.1080/00387017708065032

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Electronic (ultraviolet and visible), infrared, far infrared, and Raman spectra are listed for selected aliphatic and aromatic carbodiimides. Analysis of the spectral bands associated with the aliphatic substances are presented. Also included are the results of physical property measurements (dipole moment, vapor pressure, density, and surface tension) associated with several of the alkyl carbodiimides. In addition, a relationship is presented that correlates the v(C-C) modes of the alkyl carbodiimides, alkyl chlorides, alkyl isocyanates, alkyl isothiocyanates, and alkanes. This expression has the form v(C-C) = A(R)m, where A and m are constant terms and R represents a variable that is based upon mass ratios.

ISSN:0038-7010    

DOI:10.1080/00387017708065033

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Many13C-NMR studies dedicated to the π-(Arene)-tri-carbonylchromium(o) complexes are concerned with the origin of the large upfield shifts of the aromatic carbons on the coordination to the chromiumtricarbonyl group. This effect is not yet completely understood and various hypotheses have been formulated to justify it (1)(2)(3) (4).

ISSN:0038-7010    

DOI:10.1080/00387017708065034

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The magnetic circular dichroism (MCD) and absorption spectra of some p-disubstituted benzenes possessing both electron-donating and accepting groups were measured. The electronic spectra of the above compounds are characterized by the appearance of two absorption bands, one of which appears at 25000–40000 cm−1region with large intensity, and another at 40000–50000 cm−1region with rather small intensity. These absorption bands, especially the latter one, have been investigated by means of the MCD spectra and molecular orbital calculations based on the Pariser-Parr-Pople method.

ISSN:0038-7010    

DOI:10.1080/00387017708065035

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A new sesquiterpene lactone, fasciculide-A, was isolated from the chloroform extract of the leaves ofVernonia fasciculataMichx. The structure of fasciculide-A, 1, is deduced by interpretation of the spectroscopic data.

ISSN:0038-7010    

DOI:10.1080/00387017708065036

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

13C NMR chemical shifts of tropolone, tropolone methyl ether and colchicine are reported. The various carbon resonances have been assigned on the basis of substituent effects on benzene shifts, intensities, multiplicities generated in SFORD spectra and the comparison with structurally related compounds like tropolone and tropolone methyl ether.

ISSN:0038-7010    

DOI:10.1080/00387017708065037

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0038-7010    

DOI:10.1080/00387017708065030

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor