Synthesis and properties of hydrotris(pyrazolyl)borate (Tp) ruthenium complexes with benzophenone imine: X-ray crystal structure of [TpRu(HN=CPh2)(PEt3)2][BPh4]
摘要:
The complexes [TpRuCl(dippe)] (dippe = 1,2-bis(diisopropylphosphino)ethane) and [TpRuCl(PEt3)(2)] react with HN=CPh2 and NaBPh4 in MeOH affording the cationic mononuclear imine derivatives [TpRu(HN=CPh2)(dippe)][BPh4] and [TpRu(HN=CPh2)(PEt3)(2)][BPh4], respectively. The X-ray crystal structure of the latter has been determined. The reaction of [TpRuCl(PMePr2)((MeCN)-C-i)] with HN=CPh2 led to the neutral imine derivative [TpRuCl((PMePr2)-Pr-i)(HN=CPh2)], which adds a second imine ligand upon chloride dissociation affording the cationic bis(imine) complex [TpRu((PMePr2)-Pr-i)(HN=CPh2)(2)](+). The cationic complexes [TpRu(HN=CPh2)(dippe)][BPh4] and [TpRu(HN=CPh2)(PE3)(2)][BPh4] react with KOBut in tetrahydrofuran yielding the neutral metalated species [TpRu(sigma-eta(1)-C6H4C(Ph)=NH)(dippe)] and the phenyl complex [TpRu(sigma-eta(1)-C6H5)(PEt3)(2)], respectively. All compounds were characterized by IR, NMR and microanalysis. (C) 2000 Elsevier Science S.A. All rights reserved.
Isomerization of Internal Alkynones to Vinylidenes in Tris(pyrazolyl)borate Ruthenium Complexes. Solution and Solid-State Kinetics
作者:Isaac de los Ríos、Emilio Bustelo、M. Carmen Puerta、Pedro Valerga
DOI:10.1021/om100084x
日期:2010.4.12
Internal alkynones of the type PhC CCOR (R Ph, Me) undergo thermal isomerization to disubstituted vinylidenes, Ru=C=C(COR)Ph in the coordination sphere of tris(pyrazolyl)borate ruthenium complexes. The treatment of [TpRuCl((PPr2Me)-Pr-i)(MeCN)] and [TpRuCI((Pr2PNHPy)-Pr-i)] with NaBAr4F (Ar-F = 3,5-bis(trifluoromethyl)phenyl) and the corresponding alkynone yields eta(1)-O-ketone complexes as kinetic products. These species are metastable and spontaneously isomerize to disubstituted vinylidenes both in solution and in the solid state. Kinetic studies in solution show that the isomerization rate is first-order in the concentration of the ketone complex, and thus the activation parameters have been obtained from Eyring plots. A concerted sigmatropic 1,2-acyl shift is proposed as the key step. The isomerization in the solid-state has been studied by IR spectroscopy and the results interpreted with the Avrami-Erofeev model. The X-ray structure of a disubstituted vinylidene complex has been determined for the complex [TpRu=C=C(COPh)Ph}((PPr2Me)-Pr-i)(MeCN)][BAr4F].