Vapor-phase processable novel nonplanar donor-acceptor quateraryls for blue OLEDs

A novel series of thermally stable blue light emitting quateraryls with a piperidine-donor and a nitrile acceptor was prepared from a ketene-S,S-acetal under mild conditions without using an organometal catalyst. The performance of a blue quateraryl 6e was investigated by fabricating a multilayer OLED with a configuration of ITO/PEDOT:PSS (40 nm)/quateraryl (60 nm)/BCP (6 nm)/Alq(3) (20 nm)/LiF (0.5 nm)/Al (200 nm), which exhibited blue emission with a low turn on voltage of 4 V at a brightness of 0.22 cd/m(2).