Transition metal complexes with carboranylphosphine ligands

Synthesis of a carborane-substituted bis(phosphanido) cobaltate(i), ligand substitution, and unusual P4fragmentation

“…X-ray crystallographic analysis (vide infra) revealed the structure of the complex dianion [rac-9] 2 ⁻, which features a bridging, open-chain In all complexes, the C−C bond within the ortho-carborane backbone is in the typical range for carborane-substituted bis(phosphane) complexes. 27,50 In the case of the complex anions [rac-1] − , [rac-6] − and [rac-9] 2− , the Co−P bonds formed by the bis(phosphanido) ligand are in the range of single bonds, [51][52][53][54][55][56][57][58][59] and significantly elongated compared to IV (2.1437(5) Å), consistent with the lower oxidation state of the metal (vide infra). For these complexes, the sums of bond angles around the phosphorus atoms range from 328.5(2)°([rac-6] − ) to 340.7( 7)° ([rac-9] 2− ), showing significant pyramidalisation.…”

Ligand-Enabled Sustainable Gold Catalysis

“…Lavallo and co-workers investigated the efficiency of carborane-substituted phosphine ligands in gold catalysis . Interestingly, a perchlorinated-carba- closo -dodecarborate-substituted phosphine–gold­(I) catalyst ( Au1 ) was found to be highly efficient for the hydroamination of alkynes 3b to deliver 3c with just 10 ppm of loading with TONs up to 95,000 (Scheme ).…”

Effect of Nature of Substituents on Coordination Properties of Mono- and Disubstituted Derivatives of Boron Cluster Anions [BnHn]2– (n = 10, 12) and Carboranes with exo-Polyhedral B–X Bonds (X = N, O, S, Hal)

“…In complexation reactions, there are a great number of complexes with derivatives containing C-X exo-polyhedral bonds. Thus, carboranylphosphine ligands (with C-P exo-polyhedral bonds) are generalized in a recent review [62]; chalcogenocarboranes with C-X bonds (X = S, Se, Te) were summarized [112-…”

“…The boron atoms in carboranes have a lower negative charge as compared to boron clusters; therefore, their ability to act as a donor of electronic density reduces. In this case, there are the following ways to form complexes with carboranes: (i) the formation of a B-Hg bond during electrophilic mercurization, which proceeds to the position furthest from the carbon atoms (actually, formation of a C-Hg bond is also possible) (see review [57] and references thereof); (ii) B-H activation with the formation of a B-M bond in the presence of a substituent with a donor atom in the ortho position acting as a ligand (the substituent is usually attached to the carbon atom); therefore, activation of neighboring positions is observed (see reviews [58,59] and recent articles [60,61]); (iii) coordination by a substituent, as a rule, attached to the carbon atom of carborane cage (see, for example, review [62]).…”