Molecular Modelling: Ein Beitrag zum Verständnis der katalytischen enantioselektiven Hydrovinylierung von Styrol / Molecular Modelling: A Contribution to the Understanding of the Catalytic Enantioselective Hydrovinylation of Styrene

The hydrovinylation of styrene can be catalyzed by the addition of phosphane-modified Ni(II) compounds with high reactivity and enantioselectivity if the azaphospholene 1 is used as P-component of the catalysts. Until recently the industrial applications of 1 have been hampered by its difficult synthesis. To search for easier to synthesize, but equally well catalyzing derivatives of 1 a molecular modelling study was carried out. Based on already experimentally tested and structurally characterized azaphospholenes a model is developed, which not only leads to a better understanding of the catalytic process and but also to a relatively easy way to predict catalytic properties in these systems. Using an extended, customized valence force field several new derivatives of 1 have been tested. Their predicted and experimentally determined catalytic properties are in good agreement. The X-ray structures of the phenyl-substituted, monomeric azaphospholene 13, which hitherto results in the second best catalyst, and of its precursor 19 are presented.

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Evidence for twisted norbornanes. X-ray diffraction and valence force-field calculations

Journal of the American Chemical Society ◽

10.1021/ja00710a036 ◽

1970 ◽

Vol 92 (7) ◽

pp. 1995-1999 ◽

Cited By ~ 51

Author(s):

C. Altona ◽

Muttaiya. Sundaralingam

Keyword(s):

Force Field ◽

X Ray Diffraction ◽

Force Field Calculations ◽

Valence Force ◽

X Ray ◽

Valence Force Field

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Gitterschwingungsspektren

Zeitschrift für Naturforschung A ◽

10.1515/zna-1976-0727 ◽

1976 ◽

Vol 31 (7) ◽

pp. 847-852 ◽

Cited By ~ 20

Author(s):

H. D. Lutz ◽

P. Willich ◽

H. Haeuseler

Keyword(s):

Force Field ◽

Long Range ◽

Force Constants ◽

The Other ◽

Valence Force ◽

Normal Coordinates ◽

Valence Force Field ◽

Symmetry Coordinates ◽

Ir Frequencies ◽

Good Agreement

Abstract Force constants and normal coordinates of MnS2 , FeS2 , RuS2, RuSe2, RuTe2, OsS2 and PtP2 are calculated based on the five ir active vibrations of the pyrite lattice. By setting up a valence force field consisting of short and long range M -X, X2 -X2 and M -M stretching constants it has proved possible to obtain good agreement between experimental and calculated frequencies with expection of FeS2 and RuS2 . The force constants corresponding to the shortest metal chalcogen distances (MnS2: 0.30, RuSe2: 0.88, RuTe2: 0.62, OsS2: 1.32, PtP2: 1.22 mdyn/Å) are mainly responsible for the ir frequencies. For RuSe2 and RuTe2, the forces between adjacent X2 groups are not negligible. Whereas the force constants of OsS2 and PtP2 are of comparable strength, the forces in MnS2 are significantly weaker than those in the other compounds. The normal coordinates of MnS2, OsS2 and PtP2 , and RuSe2 and RuTe2 show significant differences according to both the contribution of the 6 symmetry coordinates to the 5 ir active vibrations and the assignment of the spectra.

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Vibrational Spectra and Normal Coordinate Calculations of Chlorophosphazene Compounds. II. Octachlorocyclotetraphosphazene

Applied Spectroscopy ◽

10.1366/0003702824638656 ◽

1982 ◽

Vol 36 (3) ◽

pp. 272-277 ◽

Cited By ~ 6

Author(s):

J. Zarian ◽

P. C. Painter ◽

M. M. Coleman

Keyword(s):

Force Field ◽

Vibrational Spectra ◽

Normal Modes ◽

Normal Coordinate ◽

Valence Force ◽

Valence Force Field ◽

Good Agreement

Vibrational spectra and normal coordinate calculations of octachlorocyclotetraphosphazene (OCTP) are presented. A common valence force field for the two conformers (T and K forms) of OCTP has been developed. A good agreement between the observed and calculated frequencies of OCTP was obtained and the assignments of the normal modes are discussed.

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The vibrational spectra of some phenylmercuric halides and diphenylmercury

Australian Journal of Chemistry ◽

10.1071/ch9771905 ◽

1977 ◽

Vol 30 (9) ◽

pp. 1905 ◽

Cited By ~ 8

Author(s):

CG Barraclough ◽

GE Berkovic ◽

GB Deacon

Keyword(s):

Force Field ◽

Raman Spectra ◽

Infrared Spectra ◽

Vibrational Spectra ◽

Infrared And Raman Spectra ◽

Normal Coordinate ◽

Valence Force ◽

Valence Force Field ◽

Phenylmercuric Chloride ◽

Good Agreement

The Raman spectra of phenylmercuric chloride, phenylmercuric bromide, phenylmercuric iodide and diphenylmercury, and the infrared and Raman spectra of diphenylmercury in solution are reported. Using the previously reported infrared spectra of these compounds, vibrations were assigned, normal coordinate analyses were performed and frequencies were calculated using a valence force field. Good agreement was achieved between observed and calculated frequencies. The structure of diphenyl-mercury in solution is discussed.

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Schwingungsspektren und Kraftkonstanten der Hexacyano-Komplexe des Mangan(I), Technetium(I) und Rhenium(I) / Vibrational Spectra and Force Constants of the Hexacyano Complexes of Mangan(l), Technicium(I) and Rhenium(l)

Zeitschrift für Naturforschung A ◽

10.1515/zna-1972-8-905 ◽

1972 ◽

Vol 27 (8-9) ◽

pp. 1193-1196 ◽

Cited By ~ 8

Author(s):

W. Krasser ◽

K. Schwochau

Keyword(s):

Force Field ◽

Raman Spectra ◽

Vibrational Spectra ◽

Point Group ◽

Force Constants ◽

Irreducible Representations ◽

Infrared And Raman Spectra ◽

Valence Force ◽

Valence Force Field ◽

Complex Salts

The infrared and Raman spectra of the complex salts K5[Mn(CN)6], K5[Tc(CN)6] and K5[Re(CN)s] have been recorded in the range from 4000 to 40 cm-1. All expected fundamental vibrations have been observed and could be assigned to the irreducible representations of the symmetry point group Oh . The calculation of the force constants is based on the concept of the generalized valence force field. The low CN-valence force constants indicate the relatively strong Π-bonding character of the metal carbon bond, which is especially pronounced for K5[Tc(CN)6).

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Rotational isomerism, structure and vibrational assignment of methoxyallene: joint IR and Raman investigation and non-empirical MO-SCF and valence force field calculations

Journal of Molecular Structure ◽

10.1016/0022-2860(89)85007-0 ◽

1989 ◽

Vol 196 ◽

pp. 79-99 ◽

Cited By ~ 6

Author(s):

Augusto Rastelli ◽

Enzo Gallinella ◽

Marina Burdisso

Keyword(s):

Force Field ◽

Rotational Isomerism ◽

Vibrational Assignment ◽

Force Field Calculations ◽

Valence Force ◽

Valence Force Field ◽

Ir And Raman

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Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von cis-[ReCl4X2]2-, X = NCS, NCSe / Crystal Structures, Vibrational Spectra and Normal Coordinate Analysis of cis-[ReCl4X2]2-, X = NCS, NCSe

Zeitschrift für Naturforschung B ◽

10.1515/znb-1998-1117 ◽

1998 ◽

Vol 53 (11) ◽

pp. 1329-1334 ◽

Cited By ~ 1

Author(s):

L. Homolya ◽

S. Strueß ◽

W. Preetz

Keyword(s):

Crystal Structures ◽

Normal Coordinate Analysis ◽

X Ray Diffraction ◽

Normal Coordinate ◽

Triclinic Space Group ◽

Valence Force ◽

Space Group ◽

X Ray ◽

Valence Force Field ◽

Ir And Raman

The crystal structures of cis-(n-Bu4N)2[ReCl4(NCS)2] (triclinic, space group P1̅, a = 11,245( 1), b = 20.174(3), c = 21.320(8) Å, a =109.06(2), β = 96.46(2), γ = 98.22(5)°, Z = 4) and cis-(Ph4P)2[ReCl4(NCSe)2]·2CH2Cl2 (triclinic, space group P1̅, a = 10.341(2), b = 13.436(3), c = 19.616(4) Å, α = 92.70(2), β = 92.02(2), γ = 89.99( 1)°, Z= 2) have been determined by single crystal X-ray diffraction analysis. Both ambidentate ligands NCS and NCSe are bonded via the N atom. Using the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis based on a modified valence force field. The valence force constants fd(ReN) are 1,78(NCS) and 1,79(NCSe) mdyn/ Å.

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