Zhang Qian-Feng, Lam Tony C H, Yi Xiao-Yi, Chan Eddie Y Y, Wong Wai-Yeung, Sung Herman H Y, Williams Ian D, Leung Wa-Hung
Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
Chemistry. 2004 Dec 17;11(1):101-11. doi: 10.1002/chem.200400853.
Treatment of titanyl sulfate in about 60 mM sulfuric acid with NaL(OEt) (L(OEt) (-)=(eta(5)-C(5)H(5))Co{P(O)(OEt)(2)}(3)) afforded the mu-sulfato complex [(L(OEt)Ti)(2)(mu-O)(2)(mu-SO(4))] (2). In more concentrated sulfuric acid (>1 M), the same reaction yielded the di-mu-sulfato complex [(L(OEt)Ti)(2)(mu-O)(mu-SO(4))(2)] (3). Reaction of 2 with HOTf (OTf=triflate, CF(3)SO(3)) gave the tris(triflato) complex [L(OEt)Ti(OTf)(3)] (4), whereas treatment of 2 with Ag(OTf) in CH(2)Cl(2) afforded the sulfato-capped trinuclear complex [{(L(OEt))(3)Ti(3)(mu-O)(3)}(mu(3)-SO(4)){Ag(OTf)}][OTf] (5), in which the Ag(OTf) moiety binds to a mu-oxo group in the Ti(3)(mu-O)(3) core. Reaction of 2 in H(2)O with Ba(NO(3))(2) afforded the tetranuclear complex (L(OEt))(4)Ti(4)(mu-O)(6) (6). Treatment of 2 with [{Rh(cod)Cl}(2)] (cod=1,5-cyclooctadiene), [Re(CO)(5)Cl], and [Ru(tBu(2)bpy)(PPh(3))(2)Cl(2)] (tBu(2)bpy=4,4'-di-tert-butyl-2,2'-dipyridyl) in the presence of Ag(OTf) afforded the heterometallic complexes [(L(OEt))(2)Ti(2)(O)(2)(SO(4)){Rh(cod)}(2)]OTf (7), [(L(OEt))(2)Ti(O)(2)(SO(4)){Re(CO)(3)}][OTf] (8), and [{(L(OEt))(2)Ti(2)(mu-O)}(mu(3)-SO(4))(mu-O)(2){Ru(PPh(3))(tBu(2)bpy)}]OTf (9), respectively. Complex 9 is paramagnetic with a measured magnetic moment of about 2.4 mu(B). Treatment of zirconyl nitrate with NaL(OEt) in 3.5 M sulfuric acid afforded [(L(OEt))(2)Zr(NO(3))][L(OEt)Zr(SO(4))(NO(3))] (10). Reaction of ZrCl(4) in 1.8 M sulfuric acid with NaL(OEt) in the presence Na(2)SO(4) gave the mu-sulfato-bridged complex L(OEt)Zr(SO(4))(H(2)O)(mu-SO(4)) (11). Treatment of 11 with triflic acid afforded [(L(OEt))(2)Zr]OTf (12), whereas reaction of 11 with Ag(OTf) afforded a mixture of 12 and trinuclear [{L(OEt)Zr(SO(4))(H(2)O)}(3)(mu(3)-SO(4))][OTf] (13). The Zr(IV) triflato complex [L(OEt)Zr(OTf)(3)] (14) was prepared by reaction of L(OEt)ZrF(3) with Me(3)SiOTf. Complexes 4 and 14 can catalyze the Diels-Alder reaction of 1,3-cyclohexadiene with acrolein in good selectivity. Complexes 2-5, 9-11, and 13 have been characterized by X-ray crystallography.
在约60 mM硫酸中用NaL(OEt)（L(OEt)(-)=(η⁵-C₅H₅)Co{P(O)(OEt)₂}₃）处理硫酸氧钛，得到μ-硫酸根配合物[(L(OEt)Ti)₂(μ-O)₂(μ-SO₄)]（2）。在更浓的硫酸（>1 M）中，相同反应生成二-μ-硫酸根配合物[(L(OEt)Ti)₂(μ-O)(μ-SO₄)₂]（3）。2与HOTf（OTf = 三氟甲磺酸根，CF₃SO₃）反应得到三（三氟甲磺酸根）配合物[L(OEt)Ti(OTf)₃]（4），而在二氯甲烷中用Ag(OTf)处理2得到硫酸根封端的三核配合物[{(L(OEt))₃Ti₃(μ-O)₃}(μ₃-SO₄){Ag(OTf)}][OTf]（5），其中Ag(OTf)部分与Ti₃(μ-O)₃核中的一个μ-氧原子相连。2在水中与Ba(NO₃)₂反应得到四核配合物(L(OEt))₄Ti₄(μ-O)₆（6）。在Ag(OTf)存在下，用[{Rh(cod)Cl}₂]（cod = 1,5-环辛二烯）、[Re(CO)₅Cl]和[Ru(tBu₂bpy)(PPh₃)₂Cl₂]（tBu₂bpy = 4,4'-二叔丁基-2,2'-联吡啶）处理2，分别得到异金属配合物[(L(OEt))₂Ti₂(O)₂(SO₄){Rh(cod)}₂][OTf]₂（7）、[(L(OEt))₂Ti(O)₂(SO₄){Re(CO)₃}][OTf]（8）和[{(L(OEt))₂Ti₂(μ-O)}(μ₃-SO₄)(μ-O)₂{Ru(PPh₃)(tBu₂bpy)}][OTf]₂（9）。配合物9是顺磁性的，测得的磁矩约为2.4 μB。在3.5 M硫酸中用NaL(OEt)处理硝酸氧锆，得到[(L(OEt))₂Zr(NO₃)][L(OEt)Zr(SO₄)(NO₃)]（10）。在1.8 M硫酸中ZrCl₄与NaL(OEt)在Na₂SO₄存在下反应，得到μ-硫酸根桥联配合物[L(OEt)Zr(SO₄)(H₂O)]₂(μ-SO₄)（11）。用三氟甲磺酸处理11得到[(L(OEt))₂Zr][OTf]₂（12），而11与Ag(OTf)反应得到12和三核[{L(OEt)Zr(SO₄)(H₂O)}₃(μ₃-SO₄)][OTf]（13）的混合物。Zr(IV)三氟甲磺酸根配合物[L(OEt)Zr(OTf)₃]（14）通过L(OEt)ZrF₃与Me₃SiOTf反应制备。配合物4和14能以良好的选择性催化1,3-环己二烯与丙烯醛的狄尔斯-阿尔德反应。配合物2 - 5、9 - 11和13已通过X射线晶体学表征。
