  The possibility of realizing topological insulators by spontaneous formation
of electronic superstructure is theoretically investigated in a minimal
two-orbital model including both the spin-orbit coupling and electron
correlations on a triangular lattice. Using the mean-field approximation, we
show that the model exhibits several different types of charge ordered
insulators, where the charge disproportionation forms a honeycomb or kagome
superstructure. We find that the charge ordered insulators in the presence of
strong spin-orbit coupling can be topological insulators showing quantized spin
Hall conductivity. Their band gap is dependent on electron correlations as well
as the spin-orbit coupling, and even vanishes with showing the massless Dirac
dispersion at the transition to a trivial charge ordered insulator. Our results
suggest a new route to realize and control topological states of quantum matter
by the interplay between the spin-orbit coupling and electron correlations.
