scholarly journals Substituent effects on carbon-13 NMR chemical shifts of side chain carbonyl carbons of 4-substituted 1-naphthamides

1987 ◽  
Vol 98 (3) ◽  
pp. 207-212
Author(s):  
K Rajasekaran ◽  
C Gnanasekaran ◽  
T C Wong
1980 ◽  
Vol 35 (7) ◽  
pp. 934-936 ◽  
Author(s):  
R. Radeglia ◽  
S. L. Spassov ◽  
R. Stefanova ◽  
S. D. Sofia

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


1981 ◽  
Vol 59 (17) ◽  
pp. 2642-2649 ◽  
Author(s):  
Elisabeth A. Dixon ◽  
Alfred Fischer ◽  
Frank P. Robinson

19F substituent chemical shifts (SCS) are reported for a series of twenty-one 3- and 4-substituted 1-fluoromethylnaphthalenes. The fluoromethylnaphthalenes exhibit an inverse SCS dependence: electron-withdrawing substituents produce upfield shifts. The results correlate well with SCS values previously reported for substituted benzyl fluorides. Hammett correlations are poor with conjugatively electron-withdrawing substituents exhibiting weaker than expected effects in the 3-position and stronger than expected effects in the 4-position. Dual substituent parameter analysis confirms the enhanced substituent–aromatic ring resonance interaction when the substituent is in the 4-position (ρR/ρI = 2). There is no evidence for enhanced resonance interaction between fluoromethyl side-chain and aromatic ring. The 19F chemical shift of 1-fluoromethylnaphthalene is markedly temperature dependent.


2010 ◽  
Vol 185 (4) ◽  
pp. 772-784 ◽  
Author(s):  
Zaira Domínguez ◽  
Javier Hernández ◽  
Lorena Silva-Gutiérrez ◽  
Magali Salas-Reyes ◽  
Mario Sánchez ◽  
...  

1976 ◽  
Vol 31 (12) ◽  
pp. 1641-1645 ◽  
Author(s):  
Walter Grahn

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.


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