In the title compound, C26H48N2Si4, the cycloheptane ring adopts a chair conformation, while the quinolinyl ring system is almost planar [maximum deviation = 0.040 (3) Å for one of the C atoms carrying a Me3Si group]. In the crystal, in the absence of classical hydrogen bonding, the packing is dominated by van der Waals forces. One of the N-bound trimethylsilyl groups is disordered by rotation about the C—SiMe3 bond, and was modelled over two sets of sites in the ratio 0.873 (8):0.127 (8).