1H,13C and19F NMR spectroscopy of polyfluorinated ureas. Correlations involving NMR chemical shifts and electronic substituent effects

2005 ◽  
Vol 43 (5) ◽  
pp. 389-397 ◽  
Author(s):  
Antonio Abad ◽  
Consuelo Agulló ◽  
Ana C. Cuñat ◽  
Cristina Vilanova
Keyword(s):  
Nmr Spectroscopy ◽  
Chemical Shifts ◽  
Substituent Effects ◽  
Nmr Chemical Shifts

Preparation, 1H and 13C NMR, and ab initio/IGLO study of mono-O-protonated deltic acid and theoretical investigation of di-, tri-, and tetra-O-protonated deltic acids

1999 ◽  
Vol 77 (5-6) ◽  
pp. 525-529 ◽  
Author(s):  
GK Surya Prakash ◽  
Golam Rasul ◽  
George A Olah ◽  
Ronghua Liu ◽  
Thomas T Tidwell
Keyword(s):  
Nmr Spectroscopy ◽  
Ab Initio ◽  
Theoretical Investigation ◽  
13C Nmr ◽  
Chemical Shifts ◽  
1H And 13C Nmr ◽  
Nmr Chemical Shifts ◽  
Molar Solution ◽  
Protonated Species ◽  
C Nmr

The hitherto elusive mono-O-protonated deltic acid C3O3H3+ was prepared by protolysis of di-tert-butoxy deltate in FSO3H-SO2ClF and in FSO3H:SbF5 (Magic Acid; 1:1 molar solution) in SO2ClF as solvent at -78°C and was characterized by 1H and 13C NMR spectroscopy. The structure and NMR chemical shifts were also calculated by the ab initio/IGLO method. No NMR evidence was found for persistent di-O-protonated deltic acid under these conditions, although a limited equilibrium with the mono-O-protonated species can be involved. Di-, tri-, and tetra-O-protonated deltic acids were also studied by ab initio/IGLO method.Key words: protonated deltic acid, aromaticity, superacids, NMR spectroscopy, ab initio and IGLO calculations.

Substituent Effects on 31P NMR Chemical Shifts and 1JP–Se of triarylselenophosphates

2010 ◽  
Vol 185 (4) ◽  
pp. 772-784 ◽  
Author(s):  
Zaira Domínguez ◽  
Javier Hernández ◽  
Lorena Silva-Gutiérrez ◽  
Magali Salas-Reyes ◽  
Mario Sánchez ◽  
...  
Keyword(s):  
31P Nmr ◽  
Chemical Shifts ◽  
Substituent Effects ◽  
Nmr Chemical Shifts

scholarly journals Substituenteneinflüsse auf die 13C–NMR-chemischen Verschiebungen cis- und trans-konfigurierter Trimethincyanine / Substituent Effects on the 13C NMR Chemical Shifts of Trimethincyanines with cis and trans Configuration

1976 ◽  
Vol 31 (12) ◽  
pp. 1641-1645 ◽  
Author(s):  
Walter Grahn
Keyword(s):  
13C Nmr ◽  
Chemical Shifts ◽  
Substituent Effects ◽  
Electron Systems ◽  
Coupling Constant ◽  
Electronic Effects ◽  
Nmr Chemical Shifts ◽  
Monosubstituted Benzenes ◽  
Cis And Trans ◽  
C Nmr

The 13C NMR chemical shifts of fifteen 6 substituted 2,3-dihydro-1,4-diazepinium salts (cis trimethincyanines) (1) and twelve 2 substituted bis(dimethylamino)trimethinium salts (trans trimethincyanines) (2) have been determined. A comparison of the substituentinduced shifts (13C SCS) of 1 and 2 allows no distinction between steric and electronic effects. In the three 6 п-electron systems 1, 2 and monosubstituted benzenes the 13C SCS are similar for the substituent bearing carbon atoms. A surprisingly large 4JFCCNC coupling constant has been observed.

Die Weiterleitung von substituenten- induzierten 13C-NMR-chemischen. Verschiebungen in para-substituierten 3-Phenylpropansäure-methylestern / The Transmission of Substituent-Induced 13C NMR Chemical Shifts in para-Substituted 3-Phenyl Propanoic Acid Methyl Esters

1980 ◽  
Vol 35 (7) ◽  
pp. 934-936 ◽  
Author(s):  
R. Radeglia ◽  
S. L. Spassov ◽  
R. Stefanova ◽  
S. D. Sofia
Keyword(s):  
13C Nmr ◽  
Chemical Shifts ◽  
Methyl Esters ◽  
Substituent Effects ◽  
Side Chain ◽  
Parameter Method ◽  
Propanoic Acid ◽  
Nmr Chemical Shifts ◽  
13C Nmr Chemical Shifts ◽  
Acid Methyl

Carbon-13 chemical shifts have been measured of para-substituted 3-phenyl propanoic acid methyl esters. The substituent-induced 13C shifts of the side chain were related to Hammett substituent effects by the dual substituent parameter method. The transmission of substituent effects and the factors that influence 13C shifts are discussed

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