The first amine-dicarboxyboranes and their dimethyl esters are synthes
ized from amine-dicyanoboranes via [amine-bis(ethylnitrilium)hydroboro
n(2+)] tetrafluoroborates, amine-bis(C-hydroxy-N-ethyliminium)hydrobor
on(2+)] cations and amine-bis(N-ethylcarbamoyl)boranes; C-methoxy-N-et
hyliminium groups adjacent to boron undergo unusual hydrolysis.