Hydrogen-deuterium exchange between TpRu(PMe3)(L)X (L = PMe3 and X = OH, OPh, Me, Ph, or NHPh; L = NCMe and X = Ph) and deuterated arene solvents: evidence for metal-mediated processes.
At elevated temperatures (90-130 degrees C), complexes of the type TpRu(PMe3)2X (X = OH, OPh, Me, Ph, or NHPh; Tp = hydridotris(pyrazolyl)borate) undergo regioselective hydrogen-deuterium (H/D) exchange with deuterated arenes. For X = OH or NHPh, H/D exchange occurs at hydroxide and anilido ligands, respectively. For X = OH, OPh, Me, Ph, or NHPh, isotopic exchange occurs at the Tp 4-positions with only minimal deuterium incorporation at the Tp 3- or 5-positions or PMe3 ligands. For TpRu(PMe3)(NCMe)Ph, the H/D exchange occurs at 60 degrees C at all three Tp positions and the phenyl ring. TpRu(PMe3)2Cl, TpRu(PMe3)2OTf (OTf = trifluoromethanesulfonate), and TpRu(PMe3)2SH do not initiate H/D exchange in C6D6 after extended periods of time at elevated temperatures. Mechanistic studies indicate that the likely pathway for the H/D exchange involves ligand dissociation (PMe3 or NCMe), Ru-mediated activation of an aromatic C-D bond, and deuteration of basic nondative ligand (hydroxide or anilido) or Tp positions via net D+ transfer.
Feng
Yuee
Y
Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA.
Lail
Marty
M
Foley
Nicholas A
NA
Gunnoe
T Brent
TB
Barakat
Khaldoon A
KA
Cundari
Thomas R
TR
Petersen
Jeffrey L
JL
D019187:Cadmium Compounds / Q000737:chemistry; D003903:Deuterium / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D008024:Ligands; D008698:Mesylates / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008854:Microscopy, Electron; D009942:Organometallic Compounds / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry; D018036:Selenium Compounds / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D013057:Spectrum Analysis; D013696:Temperature
C471689:(hydridotris(pyrazolyl)borate)rhenium(carbonyl)(1-methylimidazole)(eta2-benzene); D019187:Cadmium Compounds; D008024:Ligands; D008698:Mesylates; D008670:Metals; D009942:Organometallic Compounds; D018036:Selenium Compounds; D012997:Solvents; D012428:Ruthenium; D006859:Hydrogen; C058667:cadmium selenide; D003903:Deuterium; C012077:trifluoromethanesulfonic acid