Synthesis and NLO properties of chromophores with calix[4] arene and ring locked

The new chromophore molecules with nonlinear optical (NLO) properties were prepared by Knoevenagel condensation from diformyl calix[4]arene and isophorone derivatives in the presence of piperidine and acetic acid, respectively. In these chromophore calix[4]arenes, the ring-locked trienes were employed as the conjugation bridge and electron acceptor in D-'pi'-A units. Nuclear magnetic resonance (NMR) spectra indicate that the non-conjugated D-'pi'-A units can be oriented at nearly the same direct