The reaction of the low-coordinate quadruply-bonded dimolybdenum complex Mo2[μ,κ2-PhB(N-2,6-iPr2C6H3)2]2 (1) with Cp*Fe(η5-E5) (E = P, As) gives two trinuclear species Cp*Fe(μ3,η5:2:2-E5)Mo2[μ,κ2-PhB(N-2,6-iPr2C6H3)2]2 (E = P (4) and As (5)). 4 undergoes facile isomerisation upon heating to give Cp*FeMo2[κ2-PhB(N-2,6-iPr2C6H3)2](μ3,κ:κ:η2-P2)[μ3,κ:κ:η3κ-P3PhB(N-2,6-iPr2C6H3)2] (6), where the FeMo2P5 core motif displays a cubane-like structure.