A Rationale for the Linear Correlation of Aryl Substituent Effects in Iron(0) Tricarbonyl Complexes Containing α,β-Unsaturated Enone (Chalcone) Ligands

2007 ◽  
Vol 26 (25) ◽  
pp. 6354-6365 ◽  
Author(s):  
Benjamin E. Moulton ◽  
Anne K. Duhme-Klair ◽  
Ian J. S. Fairlamb ◽  
Jason M. Lynam ◽  
Adrian C. Whitwood
Keyword(s):  
Linear Correlation ◽  
Substituent Effects ◽  
Aryl Substituent

Carbon magnetic resonance studies of some phenyl, furyl and thienyl organometallics. Some comments on carbon-metal scalar coupling

1974 ◽  
Vol 27 (2) ◽  
pp. 417 ◽  
Author(s):  
D Doddrell ◽  
KG Lewis ◽  
CE Mulquiney ◽  
W Adcock ◽  
W Kitching ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Chemical Shifts ◽  
Substituent Effects ◽  
Coupling Constants ◽  
Scalar Coupling ◽  
Coupling Constant ◽  
Aryl Substituent ◽  
Magnetic Resonance Studies ◽  
Thienyl Group ◽  
13C Chemical Shift

13C chemical shift variations within a series of phenyl, furyl and thienyl Group IVB organometallics appear to be best understood in terms of the usual alkyl and aryl substituent effects on 13C chemical shifts and not variations in dπ ?pπ metal-aryl interactions. Large changes in 13C-metal scalar coupling constants have been observed suggesting that other factors besides the s-character of the carbon-metal bond is responsible in determining the coupling constant.

The basis of aryl substituent effects on charge-transfer absorption intensities

1986 ◽  
Vol 25 (9) ◽  
pp. 1329-1333 ◽  
Author(s):  
Carol C. Phifer ◽  
David R. McMillin
Keyword(s):  
Charge Transfer ◽  
Substituent Effects ◽  
Aryl Substituent

ChemInform Abstract: ARYL SUBSTITUENT EFFECTS UPON THE THERMAL ISOMERIZATION OF N-ALKYLOXAZIRIDINES TO NITRONES

1984 ◽  
Vol 15 (36) ◽  
Author(s):  
D. R. BOYD ◽  
P. B. COULTER ◽  
W. J. HAMILTON ◽  
W. B. JENNINGS ◽  
V. E. WILSON
Keyword(s):  
Substituent Effects ◽  
Thermal Isomerization ◽  
Aryl Substituent

scholarly journals Notable Substituent Effects on the Rate Constant of Thermal Denitrogenation of Cyclic Azoalkanes: Strong Evidence for a Stepwise Denitrogenation Mechanism

2010 ◽  
Vol 63 (12) ◽  
pp. 1615 ◽  
Author(s):  
Chizuko Ishihara ◽  
Manabu Abe
Keyword(s):  
Rate Constant ◽  
Linear Correlation ◽  
Strong Evidence ◽  
Bond Cleavage ◽  
Relative Rate ◽  
Substituent Effects ◽  
Relative Rate Constant ◽  
Rate Determining Step ◽  
Singlet Diradicals ◽  
Type Radical

The thermal denitrogenation rates (k) of a series of 7,7-dimethoxy-1,4-diaryl-2,3-diazabicyclo[2.2.1]hept-2-ene derivatives 2 with a variety of aryl groups (p-CNC6H4, C6H5, p-MeC6H4, p-MeOC6H4) were determined to investigate the denitrogenation mechanism. A linear correlation (r = 0.988) between the relative rate-constant (log krel) of the denitrogenation reaction and Arnold’s σα• parameter for benzylic-type radical-stabilization was observed. However, the relative rate-constant was not correlated with the substituent effect on the lifetime of the resulting singlet diradicals DR2. These results indicate that the rate-determining step of denitrogenation of 7,7-dimethoxy-2,3-diazabicyclo[2.2.1]hept-2-ene derivatives involves stepwise C–N bond cleavage.

Sign in / Sign up

Export Citation Format

Share Document