Element–Hydrogen Bond Activations at Cationic Platinum Centers To Produce Silylene, Germylene, Stannylene, and Stibido Complexes

Abstract

Reactions of [(dippe)PtMe(Et 2 O)][BAr f 4 ] (4[BAr f 4 ], dippe = 1,2-bis(diisopropylphosphino)ethane; Ar f = 3,5-(CF 3 ) 2 C 6 H 3 ) with Mes 2 EH 2 (Mes = mesityl) liberate methane and produce silylene, germylene, or stannylene products [(dippe)Pt(H)EMes 2 ][BAr f 4 ] (E = Si, 1[BAr f 4 ]; Ge, 8; Sn, 9). In contrast, treatment of 4[BAr f 4 ] with tertiary silanes HSiR 3 (R = Ph, Et, OEt) failed to give the expected cationic silyl complexes but instead produced the bridging hydride [(dippe)Pt(μ-H)] 2 [BAr f 4 ] 2 (10) along with the corresponding disilane Si 2 R 6 . Complex 10 reacts with primary stibines RSbH 2 (R = Mes, dmp) to afford dimeric stibido complexes [(dippe)Pt(μ-SbHR)] 2 [BAr f 4 ] 2 (R = Mes, 11; dmp, 12) via Sb−H bond activation.

Molecular Main Group Metal Hydrides

“…When this diplatinum dihydride was combined with MesSbH 2 ( 1164 ) or Ar Me6 SbH 2 ( 1165 ) dihydrogen elimination was observed to give the primary antimonide-bridged platinum dications 1248 and 1249 (eq 106 ). In 2019, Driess and coworkers demonstrated a direct route to [Li­(TMEDA)]­[AsH 2 ] by exposure of a solution of n BuLi/TMEDA mixture to arsine gas. This may prove a convenient source of [AsH 2 ] − due to the reported solubility of [Li­(TMEDA)]­[AsH 2 ] in Et 2 O, THF and toluene, unlike the commonly used donor-free salts such as K­[AsH 2 ] .…”

N‐Heterocyclic Silylenes as Ligands in Transition Metal Carbonyl Chemistry: Nature of Their Bonding and Supposed Innocence

“…Reaction of [Pd(cod)(CH 3 ) 2 ] with six equivalents of t Bu 2 NHSi H2 or four equivalents of t Bu 2 NHSi also afforded [Pd( t Bu 2 NHSi H2 ) 4 ] and [Pd( t Bu 2 NHSi) 3 ], while two NHSi equivalents were consumed during the reduction of the Pd II precursor giving a methylated disilane from t Bu 2 NHSi H2 or t Bu 2 NHSi(CH 3 ) 2 , respectively . Element–hydrogen bond activation at a cationic platinum compound and subsequent addition of the silylene gives the complex [Pt(dippe)Me( t Bu 2 NHSi)][B(C 6 F 5 ) 4 ] (dippe=1,2‐bis(di‐isopropylphosphino)ethane) …”

Identification of Reactive Intermediates Relevant to Dimethylgermylene Group Transfer Reactions of an Anthracene-Based Precursor

“…Having observed thermal loss of anthracene in the absence of a trap, we wondered if the reaction pathway might proceed through a platinum–germylene intermediate. Platinum–germylene compounds have been described previously and typically require sterically encumbering substituents on either germanium or the platinum-bound phosphine ligands to permit isolation . The thermal loss of anthracene from 1 was monitored by 1 H NMR spectroscopy to determine whether the intermediacy of a platinum germylene was kinetically plausible.…”