New method of incorporating nonhorizontal AO in semiempirical quantum-chemical calculations

The valence electronic properties of some unsubstituted and peripherally substituted oxo-titanium phthalocyanines are reported. Semiempirical quantum chemical calculations show that the nature of peripheral substituents has a strong bearing on the valence electronic properties, including the state dipole moments and absorption wavelength. The non-linear optical response was measured around the the Q-band resonance. The effect of different substituents and substitution patterns on the non-linear behaviour of the samples was determined. The combined results suggest that tuning of electronic and optical properties is effectively achieved by functionalization of the edges of the conjugated ring.

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Iodine(III)-mediated synthesis of chiral α-substituted ketones: recent advances and mechanistic insights

Pure and Applied Chemistry ◽

10.1515/pac-2016-1212 ◽

2017 ◽

Vol 89 (6) ◽

pp. 781-789 ◽

Cited By ~ 10

Author(s):

Benoit Basdevant ◽

Audrey-Anne Guilbault ◽

Samuel Beaulieu ◽

Antoine Jobin-Des Lauriers ◽

Claude Y. Legault

Keyword(s):

Quantum Chemical Calculations ◽

Quantum Chemical ◽

New Method ◽

Experimental Strategy ◽

Rapid Access ◽

Chiral Ketones ◽

Recent Advances ◽

Nucleophilic Displacement ◽

Synthetic Transformations

AbstractThe development of iodine(III)-mediated synthetic transformations has received growing interest, in particular to mediate enantioselective processes. In this class, the α-tosyloxylation of ketone derivatives using iodine(III) is a particularly powerful one, as it yields α-tosyloxy ketones – versatile chiral precursors that enable rapid access to numerous α-chiral ketones through nucleophilic displacement. Despite years of research from numerous groups, the enantioselectivities for this transformation have remained modest. Using quantum chemical calculations, we have uncovered a possible rational for the lack of selectivity. With these computational insights, we have developed an alternative experimental strategy and achieved unprecedented levels of selectivities. Applying this newfound knowledge, we have recently developed a new method to access α-halo ketones from non-ketonic precursors.

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ChemInform Abstract: Electronic Structure and Conformational Properties of the Amide Linkage. Part 9. Geometrical and Electronic Structures of N- Alkenyllactams as Determined by PE Spectroscopy and Semiempirical Quantum Chemical Calculations.

ChemInform ◽

10.1002/chin.199216038 ◽

2010 ◽

Vol 23 (16) ◽

pp. no-no

Author(s):

M. WOYDT ◽

P. RADEMACHER

Keyword(s):

Electronic Structure ◽

Quantum Chemical Calculations ◽

Electronic Structures ◽

Quantum Chemical ◽

Amide Linkage ◽

Conformational Properties ◽

Semiempirical Quantum Chemical Calculations

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Investigation of the charge state of heteroatoms in organic compounds of third-row elements by x-ray fluorescence spectroscopy 10. Correlations between values of the shifts of the k? lines of sulfur, phosphorus, and chlorine and the values of the effective charges of these atoms determined from semiempirical quantum-chemical calculations

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science ◽

10.1007/bf00965429 ◽

1991 ◽

Vol 40 (2) ◽

pp. 345-352

Author(s):

G. N. Dolenko ◽

A. L. Litvin ◽

V. P. Elin ◽

O. Kh. Poleshchuk

Keyword(s):

Fluorescence Spectroscopy ◽

Charge State ◽

Quantum Chemical Calculations ◽

Organic Compounds ◽

Quantum Chemical ◽

X Ray ◽

Effective Charges ◽

Semiempirical Quantum Chemical Calculations

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ADSORPTION MODELING OF POLYDIMETHYLSILOXANE ON SILICA: SEMIEMPIRICAL QUANTUM-CHEMICAL CALCULATIONS

Surface Review and Letters ◽

10.1142/s0218625x97000961 ◽

1997 ◽

Vol 04 (05) ◽

pp. 879-883 ◽

Cited By ~ 6

Author(s):

E. A. NIKITINA ◽

V. D. KHAVRYUTCHENKO ◽

E. F. SHEKA ◽

W. H. BARTHEL ◽

J. WEIS

Keyword(s):

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Adsorption Modeling ◽

Semiempirical Quantum Chemical Calculations

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Quantum-Chemical Investigations of 5-Bromo-2'-Deoxyuridine Derivatives with Antiviral Activity

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20060691 ◽

2006 ◽

Vol 71 (5) ◽

pp. 691-697

Author(s):

Zhivko A. Velkov ◽

Yasen Zh. Velkov ◽

Alia V. Tadjer ◽

Ivanka G. Stankova

Keyword(s):

Amino Acids ◽

Antiviral Activity ◽

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Molecular Descriptors ◽

Structure Investigation ◽

Determining Factor ◽

Semiempirical Quantum Chemical Calculations

The article describes the results of semiempirical quantum-chemical calculations for a series of 3',5'-esters of 5-bromo-2'-deoxyuridine with amino acids or peptides. These compounds were synthesized and tested for antiviral activity as potential prodrugs of the parent 5-bromonucleoside. It was not clear why only some of the compounds were active. On the basis of structure investigation and the calculated molecular descriptors, it was found that the determining factor for obtaining appropriate prodrugs of 5-bromo-2'-deoxyuridine is the lipophilicity of the esters.

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