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Methylsulfanyl‐Stabilized Rotamers of Cobalt Bis(dicarbollide)

“…The interconversion of the transoid and cisoid geometries through the controlled change of the nickel oxidation state provides the basis for the controlled rotation of the dicarbollide ligands and makes the nickel bis(dicarbollide) moiety a promising module for the design of rotation molecular switches. [5,6] However, the nickel bis(dicarbollide) system is not very stable in the presence of some Lewis bases such as 2,2′-bipyridine, [7] 1,10-phenanthroline, [8] and triphenylphosphine [9] and affords the corresponding nikelacarboranes 3,3′-L 2 -3,1,2-NiC 2 B 9 H 11 . Therefore, an exciting challenge is the design of molecular switches based on the extremely stable cobalt bis(dicarbollide) anion {[3,3′-Co(1,2-C 2 B 9 H 11 ) 2 ] -}.…”

Well‐Defined, Versatile and Recyclable Half‐Sandwich Nickelacarborane Catalyst for Selective Carbene‐Transfer Reactions

“…The central Ni atom is surrounded almost “symmetrically” by the dicarbollide ligand (Ni−C 2.124(3) and 2.116(3) Å; Ni−B 2.065(3)–2.171(3) Å) and the dppe ligand (Ni−P 2.173(8) and 2.139(8) Å) in a distorted icosahedral framework. Multiple intermolecular non‐classical hydrogen bonds [23] (C−H⋅⋅⋅Cl, C−H⋅⋅⋅π, B−H⋅⋅⋅π, C−H⋅⋅⋅H−B, C−H⋅⋅⋅H−C) and C−Cl⋅⋅⋅π interaction in crystal were found, as shown in Figures S1–3 and Table S2. The dichloromethane and the adjacent four nickelacarborane molecules are connected by two types of C55−H55A⋅⋅⋅H4A−B4, C55−H55B⋅⋅⋅H1−C1 dihydrogen bonds with the corresponding H⋅⋅⋅H distance being 2.20 Å, 2.34 Å, two kinds of C−H⋅⋅⋅Cl (H11⋅⋅⋅Cl1 2.93 Å, H16A⋅⋅⋅Cl2 2.85 Å) hydrogen bonds, and C−Cl⋅⋅⋅π interaction (Cl2⋅⋅⋅Cg2 3.57 Å, Figure S3).…”

“…The asymmetricu nit contains am olecule of 1 anda co-crystallized molecule of dichloromethane.T he centralN i atom is surroundeda lmost "symmetrically" by the dicarbollide ligand (NiÀC2 .124(3) and 2.116(3) ;N i ÀB2 .065(3)-2.171(3) ) and the dppe ligand (NiÀP2 .173(8) and 2.139(8) )i nadistorted icosahedral framework. Multiple intermolecular non-classical hydrogen bonds [23] [24] the cyclopropanation gave 21 %y ield and over 20:1 d.r. ( Entry 6).…”

Interligand Interactions in Half-Sandwich Nickelacarboranes with Phosphine Ligands: Away from Skeletal Rearrangements

“…Although the bis(triphenylphosphine) nickel complex with the parent dicarbollide ligand 3,3-(Ph 3 P) 2 -closo-3,1,2-NiC 2 B 9 H 11 is well-known, 24,35 all our attempts to prepare the complexes with substituted dicarbollide ligands 3,3-(Ph 36 It should be noted that the formation of phosphine-halide mixed complexes was also observed in the case of transition metal complexes with nido-carborane derivatives containing other charge-compensating substituents, such as the dimethylsulfonium group, 3-R 3 P-3-X-4-Me 2 S-closo-PdC 2 B 9 H 10 ]. 37 We found that the reaction of nido-carborane 7-(CyNH) 2 C-7,8-nido-C 2 B 9 H 11 with [(dppe)NiCl 2 ] in tetrahydrofuran in the presence of t-BuOK proceeds with retention of the dppe chelate coordination giving 3,3-(dppe)-1-CyN = (CyNH)C-closo-3,1,2-NiC 2 B 9 H 10 (7) as a green solid (Scheme 3).…”