Thermolysis of an in situ generated intermediate {[}(Cp{*}Ta)(2)(BH3)(2)Cl-2], 1 generated from the reaction of {[}Cp{*}TaCl4], (Cp{*} = eta(5)-C5Me5) and {[}LiBH4.thf], in presence of {[}Ru-3(CO)(12)] yielded pileo- {[}Cp{*}TaCl(mu-Cl)-B2H4Ru3(CO)(8)], 2 having two electrons fewer than seven pairs required for the observed square pyramidal geometry. Cluster 2 is the first example of an unsaturated cluster comprising early and late transition metals in a square pyramid core. This reaction also yielded {[}(Cp{*}Ta)(2)(B2H6)(B2H4Cl2)], 3 as a by-product. In addition, the reaction of {[}Cp{*}MoCl4] (Cp{*} = eta(5)- C5Me5) with {[}LiBH4.thf] in presence of excess {[}MeI] at mild condition led to the isolation of periodinated dimolybdatetraborane {[}(Cp{*}Mo)(2)B4H3I5], 4 that hints a possible existence of {[}(Cp{*}Mo)(2)B4H8]. After the isolation of periodinated 4, we extended this chemistry towards the late transition metallaborane {[}(Cp{*}Rh)(3)B4H4], 5 using {[}PtBr2] as brominating source. Although all the attempts to isolate perbrominated rhodaborane failed, we have isolated partially brominated rhodaborane clusters {[}(Cp{*}Rh)(3)(BH)-(BBr)(3)], 6 and {[}(Cp{*}Rh)(3)(BH)(3)(BBr)], 7. All the compounds were characterized by IR and H-1, B-11 and C-13 NMR spectroscopy in solution, and the solid-state structures of 2, 4 and 6 were established by crystallographic analysis.