N.m.r. studies of phenyl-substituted group 4 anions. Ion-pairing and charge delocalization vs. π-polarization effects
Abstract
The n.m.r. chemical shifts of phenyl-substituted silyl, germyl, stannyl, and plumbyl anions show that the remote phenyl carbon positions are mainly affected by π-polarizing effects and that conjugative effects are unimportant in these anionic systems.