TY - JOUR
T1 - Boron functionalization of bis(pyrazolyl)borate ligands
T2 - Molecular structures of [RuX(PPh3)2{(MeO)2B(Pz) 2}] (X = H, Cl; pz = pyrazol-1-yl)
AU - Abernethy, Robyn J.
AU - Hill, Anthony F.
AU - Smith, Matthew K.
AU - Willis, Anthony C.
PY - 2009/11/9
Y1 - 2009/11/9
N2 - The reaction of [RuCl2(PPh3)3] with K[H2B(pz)2] (pz = pyrazol-1-yl) in tetrahydrofuran at room temperature provides the known hydro/ns(pyrazolyl)borate complex [RuH(PPh 3)2{HB(pz)3}] (1b) via pyrazole scrambling. In contrast, the reaction of [RuCl2(PPh3)3] with K[H2B(pz)2] in methanol does not, as previously reported, provide [Ru(PPh3)2{H2B(pz)2} 2] but, rather, a mixture of the complexes [RuX(PPh3) 2{κ3O,N,N′-(MeO)2B(pz) 2}] (X = H (2a), Cl (2b)) and ttt-[RuCl2(HpZ) 2-(PPh3)2] (3), each of which have been structurally characterized. Although the resulting bulk admixtures of 2a,b have so far proved inseparable, treatment with mercuric chloride cleanly converts the 2a component to 2b. Heating 2b with 1,2-bis(dicyclohexylphosphino)ethane (dcpe) results in substitution of both phosphine ligands and the formation of [RuCl(dcpe){κ3O,N,N′-(MeO)2B(pz)2}] (4) in which the ruthenium-ether linkage is ultimately retained.
AB - The reaction of [RuCl2(PPh3)3] with K[H2B(pz)2] (pz = pyrazol-1-yl) in tetrahydrofuran at room temperature provides the known hydro/ns(pyrazolyl)borate complex [RuH(PPh 3)2{HB(pz)3}] (1b) via pyrazole scrambling. In contrast, the reaction of [RuCl2(PPh3)3] with K[H2B(pz)2] in methanol does not, as previously reported, provide [Ru(PPh3)2{H2B(pz)2} 2] but, rather, a mixture of the complexes [RuX(PPh3) 2{κ3O,N,N′-(MeO)2B(pz) 2}] (X = H (2a), Cl (2b)) and ttt-[RuCl2(HpZ) 2-(PPh3)2] (3), each of which have been structurally characterized. Although the resulting bulk admixtures of 2a,b have so far proved inseparable, treatment with mercuric chloride cleanly converts the 2a component to 2b. Heating 2b with 1,2-bis(dicyclohexylphosphino)ethane (dcpe) results in substitution of both phosphine ligands and the formation of [RuCl(dcpe){κ3O,N,N′-(MeO)2B(pz)2}] (4) in which the ruthenium-ether linkage is ultimately retained.
UR - http://www.scopus.com/inward/record.url?scp=70350707646&partnerID=8YFLogxK
U2 - 10.1021/om9006592
DO - 10.1021/om9006592
M3 - Article
SN - 0276-7333
VL - 28
SP - 6152
EP - 6159
JO - Organometallics
JF - Organometallics
IS - 21
ER -