The stable primary phosphine complexes trans-M(PH2Mes*)2Cl2 (1, M = Pd; 2, M = Pt; Mes* = 2,4,6-(t-Bu)3C6H2) were prepared from Pd(PhCN)2Cl2 and K2PtCl4, respectively. Reaction of Pt(COD)Cl2 (COD = 1,5-cyclooctadiene) with less bulky arylphosphines gives the unstable cis-Pt(PH2Ar)2Cl2 (3, Ar = Is = 2,4,6-(i- Pr)3C6H2; 4, Ar = Mes = 2,4,6-Me3C6H2). Spontaneous dehydrochlorination of 4 or direct reaction of K2PtCl4 with 2 equiv of PH2Mes gives the insoluble primary phosphido-bridged dimer [Pt(PH2Mes)(μ-PHMes)Cl2 (5), which was characterized spectroscopically, including solid-state 31P NMR studies. The reversible reaction of 5 with PH2Mes gives [Pt(PH2Mes)2(μ-PHMes)]2[Cl]2 (6), while PEt3 yields [Pt(PEt3)2(μ-PHMes)MCl]2 (7), which on recrystallization forms [Pt(PEt3)(μ-PHMes)Cl]2 (8). Complex 5 and PPh3 afford [Pt(PPh3)(μ-PHMes)Cl]2 (9). Addition of 1,2-bis(diphenylphosphino)ethane (dppe) to 5 gives the dicationic [Pt(dppe)(μ-PHMes)]2[Cl]22 (10-Cl), which was also obtained as the tetrafluoroborate salt 10-BF4 by deprotonation of [Pt(dppe)(PH2Mes)Cl]-[BF4] (11) with Et3N or by reaction of [Pt(dppe)(μ-OH)]2[BF4]2 with 2 equiv of PH2Mes. Complexes 8, 9, and 10-C1·2CH2Cl2·2H2O were characterized crystallographically.
|Original language||English (US)|
|Number of pages||8|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry