ENYLPHOSPHINO)ETHANE)(ETA(3)-1-ARYLALLYL)PALLADIUM TETRAFLUOROBORATES- PREPARATION, ISOMERIC EQUILIBRIA, AND CORRELATIONS OF NMR CHEMICAL-SHIFTS WITH HAMMETT SUBSTITUENT CONSTANTS
R. Malet et al., ENYLPHOSPHINO)ETHANE)(ETA(3)-1-ARYLALLYL)PALLADIUM TETRAFLUOROBORATES- PREPARATION, ISOMERIC EQUILIBRIA, AND CORRELATIONS OF NMR CHEMICAL-SHIFTS WITH HAMMETT SUBSTITUENT CONSTANTS, Journal of organic chemistry, 61(2), 1996, pp. 758-763
C-13 NMR differences of chemical shifts (delta(X) - delta(H)) of allyl
carbon atoms in a series of ans-(1-(diphenylphosphino)-2-(dimethylami
no)ethane (eta(3)-1-arylallyl)palladium tetrafluoroborates, X ranging
from NO2 to OMe, correlate very well with sigma Hammett constants for
C-1 and with sigma(+) for C-3, this carbon atom being in a trans relat
ionship with the positively charged nitrogen atom.