  The quadratic band crossing points (QBCPs) at Fermi level in two-dimension
have been proposed to be unstable under electron-electron interaction. The
possible interaction driven states include quantum anomalous Hall (QAH) state
and various nematic ordered states. In this work, motivated by the discovery of
ferromagnetic van der Waals layered metal-organic framework
CrCl$_2$(pyrazine)$_2$, we theoretically propose that the single layer of
CrCl$_2$(pyrazine)$_2$ might realize one or some of these interaction driven
states based on the QBCP protected by $C_4$ symmetry. By introducing the
short-range density-density type repulsion interactions into this system, we
have found the phase diagram depending on different interaction range and
strength. The exotic phases include the staggered chiral flux state manifesting
QAH effect, the site-nematic insulator and the site-nematic Dirac semimetal
state. The QAH state is robust against perturbations breaking the QBCP but it
is weakened by increasing temperature. The metal-organic framework is tunable
by changing the transition-metal elements, which might improve the gap size and
stability of this interaction induced QAH state.
