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Treatment of [n-Bu4N][Ru(N)Cl4] with [AgL(OEt)] (L(OEt)- = [(eta5-C5H5)Co{P(O)(OEt)2}3]-) afforded the ruthenium(VI) nitrido complex [L(OEt)Ru(N)Cl2] (1), which reacted with PPh3 to give the ruthenium(IV) phosphiniminato complex [L(OEt)Ru(NPPh3)Cl2] (2). The cyclic voltammogram of 2 displays the RuIV/III couple at ca. 0 V vs ferrocenium/ferrocene. Treatment of 1 with Me3NO afforded [LOEtRu(NO)Cl2] (3), which reacted with Ag(OTf) (OTf- = triflate) to give the chloro-bridged tetranuclear ruthenium/silver complex [L(OEt)Ru(NO)Cl2]2[Ag(OTf)]2 (4). Treatment of 1 with Na2S2O3 gave the thionitrosyl complex [L(OEt)Ru(NS)Cl2] (5). The solid-state structures of 1-4 have been established by X-ray crystallography.

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](2) (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](2) (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)](2)(mu-SO(4)) (11). Treatment of 11 with triflic acid afforded [(L(OEt))(2)Zr][OTf](2) (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.

Treatment of Na[P(O)(S-BINOL)] (S-BINOL = (S)-(−)-bi-2-naphthol) with [CpCo(CO)I2] afforded the chiral C3-symmetric oxygen tripodal ligand Na[Co{P(O)(S-BINOL)}3] (Na(1)). Recrystallization of Na(1) from acetone/toluene yielded Na(1)(C6H12O2)2 (C6H12O2 = diacetone alcohol), which has been characterized by X-ray diffraction. The solid-state structure of Na(1)(C6H12O2)2 features a six-coordinated Na with one η2 and one η1 diacetone alcohol ligand. Treatment of Na(1) with [(η6-p-cymene)RuCl2]2, [Ru(CO)Cl(CHCHPh)(PPh3)3], and [Pr(OTf)3] (OTf = triflate) afforded [(η6-p-cymene)Ru(1)][PF6] (3), [Ru(1)(CO)(CHCHPh)(PPh3)] (4), and [Pr(1)2(OTf)] (5), respectively. Treatment of Na(1) with [Cu(MeCN)4][BF4] in the presence of PhC⋮CH and Me3SiC⋮CSiMe3 afforded [Cu(1)(η2-PhC⋮CH)] (6) and [Cu(1)(η2-Me3SiC⋮CSiMe3)] (7), respectively, which have been characterized by X-ray diffraction. In both 6 and 7, the Cu atom exhibits a distorted 2 + 1 tripod ligand coordination with one Cu−O bond significantly longer than the other t...

Treatment of [Ti(O-i-Pr)(2)Cl(2)] with NaL(OEt) (L(OEt)(-) = [CpCo[P(O)(OEt)(2)](3)](-), Cp = eta(5)-C(5)H(5)) afforded [L(OEt)Ti(O-i-Pr)(2)Cl] that reacted with HCl in ether to give [L(OEt)TiCl(3)] (1). The average Ti-O and Ti-Cl distances in 1 are 1.975 and 2.293 A, respectively. Reaction of titanyl sulfate with NaL(OEt) in water followed by addition of HBF(4) afforded [L(OEt)TiF(3)] (2), the Ti-O and Ti-F distances of which are 2.020(2) and 1.792(2) A, respectively. The Zr(IV) analogue [L(OEt)ZrF(3)] (3) was prepared similarly from zirconyl nitrate, NaL(Oet), and HBF(4) in water. The Zr-O and average Zr-F distances in 3 are 2.139(2) and 1.938(2) A, respectively. Treatment of 1 with tetrachlorocatechol (H(2)Cl(4)cat) afforded [L(OEt)Ti(Cl(4)cat)Cl] (4). The average Ti-O(P), Ti-O(C), and Ti-Cl distances in 4 are 1.972, 1.926, and 2.334 A, respectively. Hydrolysis of 4 in the presence of Et(3)N yielded the mu-oxo dimer [(L(OEt))(2)Ti(2)(Cl(4)cat)(2)(mu-O)] (5). The average Ti-O(P), Ti-O(C), and Ti-O(Ti) distances in 5 are 2.027, 1.926, and 1.7977(9) A. Treatment of 1 with 1,1'-binaphthol (BINOLH(2)) in the presence of Et(3)N afforded [(L(OEt))(2)Ti(2)(mu-O)(2)(mu-BINOL)] x 2BINOLH(2) (6.2BINOLH(2)). Complex 1 is capable of catalyzing ring opening of epoxides with Me(3)SiN(3) under solvent-free conditions presumably via a Ti-azide intermediate.

Treatment of [Ru(CO)2Cl2]x with NaLOEt (LOEt−=[Co(η5-C5H5){P(O)(OEt)2}3]−) afforded [LOEtRu(CO)2Cl] (1), which reacted with AgBF4 in acetone–H2O to give [LOEtRu(CO)2(H2O)][BF4] (2). Reaction of [LOEtRu(CHCHPh)(CO)(PPh3)] with HCl gave [LOEtRuCl(CO)(PPh3)] (3), which has been characterized by X-ray crystallography. The RuC, RuP, RuCl and average RuO distances in 3 are 1.993(7), 2.2811(13), 2.376(2) and 2.137 A, respectively. Interaction of [LOEtRu(PPh3)2Cl] with CS2 and PR3 in the presence of [NH4][PF6] afforded the ruthenium(II) phosphoniodithiocarboxylate species [LOEtRu(PPh3)(η2-S2CPR3)][PF6] (R=Ph (4) or cyclohexyl (5)). Oxidation of 4 with AgBF4 yielded the ruthenium(III) complex [LOEtRu(PPh3)(η2-S2CPPh3)][BF4][PF6] (6), which has been characterized by X-ray crystallography. The RuP, average RuO and average RuS distances in 6 are 2.3978(10), 2.078 and 2.2910 A, respectively. The ruthenium(II) thiocarbonyl complex [LOEtRu(CS)Cl(PPh3)] (7) was prepared from NaLOEt and [Ru(CS)Cl2(PPh3)2]2. The RuCl, RuP, RuC and average RuO distances in 7 are 2.3681(10), 2.3043(9), 1.823(4), and 2.140 A, respectively. Treatment of 7 with AgBF4 in acetone–H2O afforded [LOEtRu(CS)(PPh3)(H2O)][BF4] (8). On the basis of the Ru(III/II) formal potential, CS was found to be a stronger π acid ligand than CO.

Dicationic Pd(II) complexes with chiral pyridine bis(oxazoline) ligands are catalysts for kinetic resolution of racemic styrene tosylazirdines. Treatment of styrene tosylaziridine with 0.5 equivalents of alcohol in the presence of the chiral Pd catalyst affords β-alkoxy tosylamide with ee up to 71%.

The treatment of HfCl(4) with NaL(OEt) (L(OEt)(-) = [(eta(5)-C(5)H(5))Co{P(O)(OEt)(2)}(3)](-)) in nitric acid afforded L(OEt)Hf(NO(3))(3) (1). Hydrolysis of 1 in acetone/water (4:1, v/v) yielded the hydroxy-bridged dimer [(L(OEt))(2)Hf(2)(H(2)O)(4)(mu-OH)(2)][NO(3)](4) (2). The treatment of (NH(4))(2)[Ce(NO(3))(6)] with 2 equiv of NaL(OEt) in water afforded (L(OEt))(2)Ce(NO(3))(2) (3), whereas that with 1 equiv of NaL(OEt) in CH(2)Cl(2) gave L(OEt)Ce(NO(3))(3) (4). While 4 is stable in organic solvents such as acetone, it was converted completely to 3 in acetone/water. The treatment of 3 with bis(p-nitrophenyl)phosphate (BNPP) afforded (L(OEt))(2)Ce[eta(1)-OPO(OR)(2)](2) (5; R = p-NO(2)C(6)H(4)), whereas the reaction of 4 with NaPO(2)(OR)(2) yielded dinuclear [L(OEt)Ce(NO(3))(2){mu-O(2)P(OR)(2)}](2) [R = p-NO(2)C(6)H(4) (6), Ph (7)]. The addition of 3 in acetone to an aqueous solution of NaH(2)PO(4) yielded the cerium(IV) dihydrogen phosphate complex (L(OEt))(2)Ce(PO(4)H(2))(2) (8). Complexes 1-5 and 7 have been characterized by X-ray crystallography. The hydrolysis of BNPP with L(OEt)M(NO(3))(3) (M = Zr, Hf, Ce) in acetone/water has been studied by (1)H NMR spectroscopy. At 25 degrees C, with [Ce] = 20[BNPP], in an acetone-d(6)/N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid (4:1, v/v) buffer solution (50 mM) (4:1, v/v), the hydrolysis of BNPP with 4 was found to exhibit first-order kinetics with a rate constant of (1.1 +/- 0.1) x 10(-3) s(-1).

Treatment of titanyl sulfate in dilute sulfuric acid with 1 equiv of NaL(OEt) (L(OEt)(-) = [(eta(5)-C(5)H(5))Co{P(O)(OEt)(2)](3)](-)) in the presence of Na(3)PO(4) and Na(4)P(2)O(7) led to isolation of [(L(OEt)Ti)(3)(mu-O)(3)(mu(3-)PO(4))] (1) and [(L(OEt)Ti)(2)(mu-O)(mu-P(2)O(7))] (2), respectively. The structure of 1 consists of a Ti(3)O(3) core capped by a mu(3)-phosphato group. In 2, the [P(2)O(7)](4-) ligands binds to the two Ti's in a mu:eta(2),eta(2) fashion. Treatment of titanyl sulfate in dilute sulfuric acid with NaL(OEt) and 1.5 equiv of Na(2)Cr(2)O(7) gave [(L(OEt)Ti)(2)(mu-CrO(4))(3)] (3) that contains two L(OEt)Ti(3+) fragments bridged by three mu-CrO(4)(2-)-O,O' ligands. Complex 3 can act as a 6-electron oxidant and oxidize benzyl alcohol to give ca. 3 equiv of benzaldehyde. Treatment of [L(OEt)Ti(OTf)(3)] (OTf(-) = triflate) with [n-Bu(4)N][ReO(4)] afforded [[L(OEt)Ti(ReO(4))(2)](2)(mu-O)] (4). Treatment of [L(OEt)MF(3)] (M = Ti and Zr) with 3 equiv of [ReO(3)(OSiMe(3))] afforded [L(OEt)Ti(ReO(4))(3)] (5) and [L(OEt)Zr(ReO(4))(3)(H(2)O)] (6), respectively. Treatment of [L(OEt)MF(3)] with 2 equiv of [ReO(3)(OSiMe(3))] afforded [L(OEt)Ti(ReO(4))(2)F] (7) and [[L(OEt)Zr(ReO(4))(2)](2)(mu-F)(2)] (8), respectively, which reacted with Me(3)SiOTf to give [L(OEt)M(ReO(4))(2)(OTf)] (M = Ti (9), Zr (10)). Hydrolysis of [L(OEt)Zr(OTf)(3)] (11) with Na(2)WO(4).xH(2)O and wet CH(2)Cl(2) afforded the hydroxo-bridged complexes [[L(OEt)Zr(H(2)O)](3)(mu-OH)(3)(mu(3)-O)][OTf](4) (12) and [[L(OEt)Zr(H(2)O)(2)](2)(mu-OH)(2)][OTf](4) (13), respectively. The solid-state structures of 1-3, 6, and 11-13 have been established by X-ray crystallography. The L(OEt)Ti(IV) complexes can catalyze oxidation of methyl p-tolyl sulfide with tert-butyl hydroperoxide. The bimetallic Ti/ Re complexes 5 and 9 were found to be more active catalysts for the sulfide oxidation than other Ti(IV) complexes presumably because Re alkylperoxo species are involved as the reactive intermediates.