0000000000286372
AUTHOR
Adrian-radu Popescu
Chelation of a proton by oxidized diphosphines
Abstract The chelation of a proton by oxidized diphosphines is studied for the first time both experimentally and theoretically. As a proof of concept the rare case where two different H-bond systems exist in one compound, H[7,8-(OP i Pr 2 ) 2 -7,8- nido -C 2 B 9 H 10 ] is reported. Based on NBO, QTAIM and ELF calculations, the P–O⋯H + ⋯O–P interactions were characterized as strong hydrogen bonds.
Intramolecular Communication in Anionic Oxidized Phosphanes through a Chelated Proton
Oxidation of the 1,2-(PR2 )2 -1,2-closo-C2 B10 H10 (R=Ph, iPr) platform with hydrogen peroxide in acetone is a two-step procedure in which partial deboronation of the closo cluster and oxidation of the phosphorus atoms occur. Based on NMR spectroscopic and kinetic data, we demonstrate that the phosphorus atoms are oxidized in the first step, followed by cluster deboronation. DFT calculations and natural-bond orbital (NBO) analysis were used to obtain insight into the electronic structures of diphosphane ortho-carborane derivatives.
Uncommon coordination behaviour of P(S) and P(Se) units when bonded to carboranyl clusters: experimental and computational studies on the oxidation of carboranyl phosphine ligands.
Oxidation of closo-carboranyl diphosphines 1,2-(PR(2))(2)-1,2-closo-C(2)B(10)H(10) (R=Ph, iPr) and closo-carboranyl monophosphines 1-PR(2)-2-R'-1,2-closo-C(2)B(10)H(10) (R=Ph, iPr, Cy; R'=Me, Ph) with hydrogen peroxide, sulfur and elemental black selenium evidences the unique capacity of the closo-carborane cluster to produce uncommon or unprecedented P/P(E) (E=S, Se) and P=O/P=S chelating ligands. When H(2)O(2) reacts with 1,2-(PR(2))(2)-1,2-closo-C(2)B(10)H(10) (R=Ph, iPr), they are oxidized to 1,2-(OPR(2))(2)-1,2-closo-C(2)B(10)H(10) (R=Ph, iPr). However, when S and Se are used, different reactivity is found for 1,2-(PPh(2))(2)-1,2-closo-C(2)B(10)H(10) and 1,2-(PiPr(2))(2)-1,2-closo-C(2)…