Metal-rich metallaboranes: An exo-Fe(CO)3 moiety linked to a cubane core is the most prominent feature of complexes [(Cp*M) 2(μ3-E)2B2H(μ-H){Fe(CO) 2}2Fe(CO)3] (M=Mo, E=S, Se; M=Ru, E=CO; Cp*=n5-C5Me5), which are the first heterobimetallic cubane-type clusters with a boride unit (see structure). © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.