Reactions of POCOP pincer palladium benzylthiolate complexes with BH3·THF: Isolation and characterization of unstable POCOP-Pd(η1-HBH3) complexes

Progress toward the Isolation of Late Metal Terminal Sulfides

“…In fact, this distance is similar to the Pd–S bridging distances in 55 (2.314(4) and 2.356(4) Å), as well as typical Pd–Cl distances (e.g., the Pd–Cl bond length in [ trans ‐Pd(Ph 3 P) 2 Cl 2 ] is 2.290(1) Å) . It is also identical to the Pd–S distance reported for the palladium hydrosulfide complex, [(POCOP)Pd(SH)] ( 56 , POCOP = 2,6‐( t Bu 2 PO) 2 C 6 H 3 ) (Pd–S = 2.369(2) Å), suggesting that the formulation of 55 may be more complex that initially surmised.…”

Coordination mode and stability of the tetrahydroborate ligand in group 10 metal pincer complexes

“…The 11 B NMR spectrum of the reaction mixture also displayed a new quintet at −29.2 ppm, which is quite similar to the 11 B resonance of the related transition metal tetrahydroborate complexes. 5–10,12,13 As a result, the expected platinum tetrahydroborate complex Pt-POCOP was very probably formed cleanly during the reaction. However, several attempts to isolate this complex failed.…”

“…The formation mechanism of Pt-POCOP in the present synthesis is probably similar to that of the reactions of POCOP pincer ligated nickel and palladium thiolate complexes with BH 3 ·THF. 6–8 The chloride complex reacts with BH 3 ·THF to form the corresponding hydride complex and generate BH 2 Cl species first; the hydride complex further reacts with BH 3 ·THF to form the expected tetrahydroborate complex. As a highly reactive species, BH 2 Cl may be converted into chloride bridged di-boron species.…”

“…We have been interested in the structures and reactivities of group 10 metal complexes supported by different types of pincer ligands. 5–11 During our investigation, we noticed that the coordination mode and reactivity of the BH 4 − auxiliary ligand in group 10 metal pincer complexes can be significantly influenced by the pincer platforms. In order to rationalize this influence comprehensively, we synthesized and characterized more nickel and platinum complexes supported by bis(phosphinite) POCOP and diphosphino-boryl PBP pincer ligands.…”

A Structure Comparison of Ni(II) Complexes Supported by PNCNP and POCOP Pincer Ligands

“…Similar phenomena were also observed for the amino hydrogen of complexes 1 b – d . The BH 4 moiety in complex 1 d gave a broad peak around −1.60 ppm in the 1 H NMR spectrum and a quintet at −36.5 ppm ( J B‐H =86 Hz) in the 11 B NMR spectrum, which are comparable to those of complex 2 d . The 31 P{ 1 H} NMR spectra displayed a singlet for all of the complexes indicating that the two i Pr 2 PNH arms are equivalent in solutions for 1 a – d .…”