Palladium and Rhodium Complexes with Planar-Chiral Carborane Ligands

Large-cage (11–13-vertex) dicarbon metallacarboranes of platinum metals with mono- and polycyclic diolefin ligands

“…In all cases, only complexes containing the ancillary COD and DIOP ligands were catalytically active [38]. Thus, in the hydrogenation of ADZA and KPL, enantiomerically pure 44a-R gave 60-62 and 23% ee of the corresponding reduction products (N-acetyl-L-phenylalanine as its methyl ester and (R)-pantolactone, respectively).…”

“…1) [38]. The stereochemistry of one of the resulting diastereomers in the solid state, viz., isomer 43a-R,R, was established by X-ray diffraction.…”

Acidic hydrolysis of N-acyl-1-substituted 3-amino-1,2-dicarba-closo-dodecaboranes

“…3-Aminocarborane 2 (150 mg, 0.64 mmol) was refluxed in a mixture of CD 3 COOD (5 mL) and concentrated DCl (5 mL) for 22 h. The reaction mixture was monitored by 1 H and 11 B NMR spectroscopy at intervals,in 4,7,15,and 22 h. …”

“…1). For convenience in the designation of the configuration of planar-chiral carboranes and their derivatives we have used the approach suggested for chiral 7,8-dicarba-nido-undecaborane derivatives [4]. The observer looks onto the plane of C 1 R-C 2 H-B 3 NHX face of carborane cage and then examines the position of substituents according to the Cahn-Ingold-Prelog rule.…”

Rhodium-catalyzed enantioselective hydrogenation of ketopantolactone

“…The reaction has been extensively studied using chiral Rh, Ru, Cr, and Ir complexes that afford at best close to 99% ee [26][27][28][29][30][31]. Chiral heterogeneous catalysts are less efficient so far.…”