A class of phase-transfer catalyst with interionic strain: insight into the bonding of disubstituted N- vs carbene-stabilized N(I)-centered cations.

The straightforward synthesis of a class of nitrogen-based phase-transfer catalysts (PTCs) having markedly dissociated anions due to interionic donor-donor "ion pair strain" and use for catalyzing benzylation and benzylic fluorination is reported. Provided also is insight into the bonding of disubstituted N- vs so-called divalent carbene-stablized N(I)-centered cations and the unprecedented finding of a cyclopropenium based C-H···πaryl interaction.