Influence of the linker length on the host-guest properties of alkoxy- and polypyridine-bridged molecular rectangles of formulae {[Re(CO)3(OC5H11)]4(L)2}, with L = 4-pyridinealdazine and 4,4′-azobis(pyridine)

► New rhenium-containing molecular rectangles have been prepared and characterized. ► Fluorescence of small hydrocarbons can be quenched by these rectangles. ► Extent of C-H⋯π interactions decreases with decreasing length of the linkers.