4,4-Di­fluoro-2,3;5,6-bis­(tetra­methylene)-4-bora-3a,4a-di­aza-s-indacene (LD540)

The title compound, C(18)H(21)BF(2)N(2), is a lipophilic dye based on a BODIPY fluoro­phore backbone, which was developed for microscopic imaging of lipid droplets; the mol­ecule has a planar BODIPY core [dihedral angle between the pyrrole rings = 2.3 (3)°] and two tetra­methyl­ene substituents at the 2,3- and 5,6-positions in a half-chair conformation. One of the tetra­methyl­ene substituents is disordered over two two sets of sites with site occupancies of 0.5. In the crystal, pairs of C—H⋯F inter­actions link the mol­ecules into inversion dimers. Neighbouring dimers are linked by further C—H⋯F inter­actions, forming an infinite array. C—H⋯π and π–π [centroid–centroid distance = 4.360 (3) Å] inter­actions are observed between the BODIPY core and the tetra­methyl­ene substituents of neighbouring dimer pairs.