Insertion of B−X (X = Cl, SMe2) Moieties into Ruthenaborane Frameworks:  Synthesis and Characterization of (η5-C5Me5Ru)2(μ-H)B4HmCln, (m, n = 4, 3; 5, 2; 7, 2), closo-1-(SMe2)-2,3-(η5-C5Me5Ru)2(μ3-H)B5HCl3, and closo-2,3-(η5-C5Me5Ru)2B6H3Cl3

The reaction of  nido -1,2-(η 5 -C 5 Me 5 Ru) 2 (μ-H) 2 B 3 H 7  (1) with the dichloroborane BHCl 2 ·SMe 2  results in the formation of three sets of B−Cl inserted metallaborane products:   nido -1,2-(η 5 -C 5 Me 5 Ru) 2 (μ-H)B 4 H 7 Cl 2  (2),  pileo -2,3-(η 5 -C 5 Me 5 Ru) 2 (μ-H)B 4 H 5 Cl 2  (three geometric isomers, 3−5), and  pileo -2,3-(η 5 -C 5 Me 5 Ru) 2 (μ-H)B 4 H 4 Cl 3  (a pair of geometric isomers, 6 and 7). When the same reaction was carried out under more forcing conditions, three new metallaborane compounds,  closo -1-(SMe 2 )-2,3-(η 5 -C 5 Me 5 Ru) 2 (μ 3 -H)B 5 HCl 3  (a pair of geometric isomers, 8 and 9) and  closo -2,3-(η 5 -C 5 Me 5 Ru) 2 B 6 H 3 Cl 3  (10), were isolated in low yield in addition to 2−7. Compounds 8 and 9 exhibit a capped-octahedral geometry, and 10 exhibits a seven-sep (skeletal electron pair) bicapped-octahedral geometry. Reaction of  nido -2,4-(η 5 -C 5 Me 5 Ru) 2 B 6 H 12  and  nido -2,3-(η 5 -C 5 Me 5 Ru) 2 B 8 H 12  with BHCl 2 ·SMe 2  results in substitution of terminal H by Cl, producing  nido -2,4-(η 5 -C 5 Me 5 Ru) 2 B 6 H 10 Cl 2  (11) and  nido -2,3-(η 5 -C 5 Me 5 Ru) 2 B 8 H 11 Cl (12) in 82% and 75% yields, respectively.