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Recently we described the synthesis and structural characterization of various dimetallaherteroborane clusters, namely nido-[(CpMo)BEClH], 1- 3; ( 1: E = S, x = 0; 2: E = Se, x = 0; 3: E = Te, x = 1). A combined theoretical and experimental study was also performed, which demonstrated that the clusters 1- 3 with their open face are excellent precursors for cluster growth reaction. In this investigation process on the reactivity of dimetallaheteroboranes with metal carbonyls, in addition to [(CpMo)BHEFe(CO)] ( 4: E = S, 6: E = Te) reported earlier, reaction of 2 with [ Fe(CO)] yielded mixed-metallaselenaborane [(CpMo)BHSeFe(CO)], 5 in good yield. The quantum chemical calculation using DFT method has been carried out to probe the bonding, NMR chemical shifts and electronic properties of dimolybdaheteroborane clusters 4- 6. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Chemistry and reactivity of dimolybdathiaborane, [(CpMo)BSH], 1, obtained from the reaction of 2-mercaptobenzothiazole, [CpMoCl] and [LiBH.thf], has been explored with dinuclear metal carbonyl [Fe(CO)]. As a result, reaction of 1 with [Fe(CO)] yielded heterometallathiaborane, [(CpMo)BHSFe(CO)], 2 in good yield. Both the new compounds have been characterized in solution by H, B and C NMR spectroscopy and the structural types were unequivocally established by X-ray crystallographic analysis of compound 2. Cluster 2 has a bicapped octahedral geometry with the {Fe(CO)} fragment occupying one of the high-connectivity cluster vertexes rather than a capping position. Interestingly, cluster 1 undergoes geometric changes (bicapped trigonal bipyramid → bicapped octahedron) on the addition of two-electron {Fe(CO)} fragment to 1. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract : Treatment of nido-[1,2-(Cp*Ru)2(μ-H)2B3H7], 1 with five equivalents of Te powder led to the isolation of diruthenium pentalene analogue [(Cp*Ru){(Cp*Ru)2B6H14}(RuCp*)], 2 and a metal indenyl complex [(Cp*Ru)2B2H6C6H3(CH3)], 3. The [(Cp*Ru)2B6H14] fragment in 2 may be considered as a true metal-boron analogue of η5-η5-pentalene ligand (C8H6) and [(Cp*Ru)B2H6C6H3(CH3)] fragment in 3 is an analogue of η5-indenyl ligand. The solid-state X-ray structures were unambiguously determined by crystallographic analysis of compounds 2 and 3. Further, the density functional theory (DFT) calculations were performed to investigate the bonding and the electronic properties of 2a (Cp analogue of 2). The frontier molecular orbital analysis of both 2a and 2b (Cp analogue of [(Cp*Ru)B8H14(RuCp*)]) reveals a lower HOMO-LUMO gap indicating less thermodynamic stability.Graphical Abstract: SYNOPSIS Treatment of nido-[1,2-(Cp∗Ru)2(μ-H)2B3H7] with Te powder led to the isolation of diruthenium pentalene analogue [(Cp*Ru){(Cp*Ru)2B6H14}(RuCp*)] and a metal indenyl complex [(Cp*Ru)2B2H6C6H3(CH3)]. [ABSTRACT FROM AUTHOR]