Reactions of nickel boranyl compounds with pnictogen–carbon triple bonds

Abstract

The catalytic conversion of unsaturated small molecules such as nitriles into reduced products is of interest for the production of fine chemicals.

Anomalous Hydroboration at a Four-Coordinate Ni(II) Diphenylvinylphosphine Complex: Geometric Impacts on Solution Equilibria

“…Incorporation of such groups has allowed for access to unique reactivity in elementary reactions such as hydride transfer, 22 oxidative addition, 23 transmetalation, 24 and small molecule activation. 25,26 Recently, we expanded the scope of our interests to include monodentate phosphine ligands, reporting access to three-coordinate dinickel( 0 We now report that reaction of trans-[Ni II (X) 2 (PPh 2 Vin) 2 ] (X = Cl) with HBCy 2 (Cy = cyclohexyl) results in an unanticipated Markovnikov addition to give a branched isomer, while X = Br results in both anticipated anti-Markovnikov hydroboration to yield a linear isomer and Markovnikov addition to give a branched isomer. We show that BH addition is guided by a B−X (X = halide) interaction, wherein the halide presumably serves in a directing capacity.…”

“…Since 2020, our group has focused on the development of diphosphine ligands containing borane moieties positioned in their secondary coordination sphere. Incorporation of such groups has allowed for access to unique reactivity in elementary reactions such as hydride transfer, oxidative addition, transmetalation, and small molecule activation. , Recently, we expanded the scope of our interests to include monodentate phosphine ligands, reporting access to three-coordinate dinickel(0) compounds having vinyldiphenylphosphine coligands, accessed by (a) reaction of [Ni­(COD) 2 ] with PPh 2 Vin (Vin = vinyl) or (b) reduction of trans -[Ni II (Br) 2 (PPh 2 Vin) 2 ] with Cp 2 Co (Cp = C 5 H 5 – ) . Beyond reductive chemistry, we were equally interested in exploring how compounds of the type trans -[Ni II (X) 2 (PPh 2 Vin) 2 ] (X = halide) reacted with conventional monohydridoboranes (HBR 2 ).…”

Ynone Co-Coordination at a Nickel Borane Complex: An Assessment of Secondary Coordination Sphere Effects

“…As part of our ongoing program on secondary coordination sphere ligand design, we have identified a family of ambiphilic diphosphines that contain Lewis acid boron-based secondary coordination spheres including tetra-, di-, − and monoborane variants. Diphosphine ligands are ubiquitous in synthetic chemistry, with slight modification leading to dramatic changes in reactivity.…”

Tridentate κ3-P,P,C iridium complexes: influence of ligand saturation on intramolecular C–H bond activation

“…As a component of our research program, we are interested in secondary coordination sphere ligand development. [27][28][29][30][31][32][33] To date, we have developed a family of ambiphilic diphosphines that contain Lewis acidic boron-based secondary coordination spheres including tetra-, 31 di-, 28,32,33 and monoboranyl 28,29 variants. In 2022, we reported on the preparation of a series of iridium(I/III) diphosphine complexes where diphosphine = the tetraboranyl ligand, 1,2-bis(di(3-dicyclohexylboranyl)propylphosphino)ethane (P 2 B Cy 4 ).…”