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1.
Tetracyanoethylene oxide (TCNEO) reacted with [CpCo(dithiolene)] (Cp = η5-cyclopentadienyl) complexes having 4-pyridyl or 3-pyridyl group to undergo a dicyanomethylation to the nitrogen atom on the pyridyl group. The reaction of [CpCo(S2C2(4Py)2)] (1) with TCNEO formed both the monodicyanomethylated [CpCo(S2C2(4Py)(4Py-C(CN)2))] (1a) and bisdicyanomethylated [CpCo(S2C2(4Py-C(CN)2)2)] (1b). [CpCo(S2C2(2Py)(4Py))] (2) reacted with TCNEO to give [CpCo(S2C2(2Py)(4Py-C(CN)2))] (2a) but no dicyanomethylation occurred on the 2-pyridyl group. 2 reacted with excess TCNEO to form the only dicyanomethylated acetylene derivative 2Py-CC-(4Py-C(CN)2) (2c), followed by a dissociation of the CpCoS2 fragment. The monodicyanomethylated [CpCo(S2C2(nPy-C(CN)2)(2-thienyl))] (n = 4 (4a) or 3 (5a)) complexes were also prepared from [CpCo(S2C2(nPy)(2-thienyl))] (n = 4 (4) or 3 (5)) and TCNEO. 1b was structurally characterized by X-ray diffraction study. The all dicyanomethylated [CpCo(dithiolene)] complexes showed the dithiolene LMCT absorption in the range of 605-644 nm (ε = 7000-9200 M−1 cm−1) and very strong absorption due to their pyridinium-dicyanomethylide moieties in near-UV region (e.g. 1b: λmax = 470 nm, ε = 43,400 M−1 cm−1). The CV of the all dicyanomethylated complexes exhibited two reduction waves. The first reduction is due to CoIII/CoII and the second one is due to the reduction of the pyridinium-dicyanomethylide moiety. The reduced 1b is stable enough for several minutes according to the visible spectroelectrochemical measurement. The ESR spectrum of 1b indicated eight hyperfine splittings due only to the interaction with the nuclear spin of cobalt (I = 7/2).  相似文献   

2.
Azido coordinated dithiolene complexes [CpCo(N3){S2C2(CO2Me)2}(S-CHR1R2)], where R1, R2 = H (4a); R1 = H, R2 = SiMe3 (4b); R1 = H, R2 = CO2Et (4c), were synthesized by the reactions of the corresponding Cl coordinated precursors [CpCo(Cl){S2C2(CO2Me)2}(S-CHR1R2)] (3a-3c) with sodium azide. The Cl coordinated complex 3d (R1, R2 = CO2Me) did not produce any N3 coordinated complexes but formed the CR1R2-bridged alkylidene adduct [CpCo{S2C2(CO2Me)2}(CR1R2)] (2d; R1, R2 = CO2Me). The structure of 4a was determined by X-ray diffraction study. In the molecular structure of 4a, the coordinated N3 ligand and CHR1R2 group were located at the same side with respect to the dithiolene ring (syn form), although the corresponding Cl precursor (3a; R1, R2 = H) was anti form. A structural conversion of syn/anti was conceivable during the Cl/N3 ligand exchange. Thermal (80 °C) and photochemical reactions (Hg lamp) of 4a-4c were performed. Among them, 4c was relatively well reacted compared with the others to form the CR1R2-bridged alkylidene adduct (2c; R1 = H, R2 = CO2Et), followed by a formal HN3 elimination, and the reaction also produced non-adduct of the cobalt dithiolene complex [CpCo{S2C2(CO2Me)2}] (1). The electrochemical 1e reduction of 4c underwent a formal N3 ligand elimination, and successive second reduction caused the CHR1R2 group elimination or reformed the CR1R2-bridged alkylidene adduct 2c.  相似文献   

3.
One-pot reaction of [CpCo(CO)2], elemental sulfur with some heterocycle-substituted alkynes (R-CC-HET) produced [CpCo(dithiolene)] complexes with 2PyOBn (2), with both 2PyOBn and 2-hydroxy-2-propyl groups (C(OH)Me2) (5), both 2Py and C(OH)Me2 (8), both 4Py and C(OH)Me2 (11), and with 4Py substituent (13). A deprotection of benzyl group (Bn) from 2 with trimethylsilyl iodide formed [CpCo(dithiolene)] with 2-pyridonyl substituent (3). Heating reaction of 8 without any base resulted in the C(OH)Me2 group elimination to form the 2-pyridylethylenedithiolate complex (9), but 11 underwent only dehydration at the C(OH)Me2 under heating. While the preparation of 5, the benzyl free complex (6) was obtained as a main product. 6 has a dithiolene-fused tricyclic pyridone skeleton. The structures of 3, 5, 6, 8, and 11 were determined by X-ray diffraction studies. Intramolecular OH?N(2Py) hydrogen bondings are found in 5 and 8, and an intermolecular OH?N(4Py) one is found in 11 at solid state. In the 2-pyridonyl complex 3, intermolecular NH?O and CH(dithiolene)?O hydrogen bondings are observed. 8 showed an intermolecular Cp?Cp face-to-face interaction. The tricyclic complex 6 exhibited lower energy electronic absorption (λmax = 668 nm) compared with the others (λmax = 562-614 nm), due to an extended π-conjugation of aromatic cobaltadithiolene ring.  相似文献   

4.
Sulfur analogues of the soluble guanylate cyclase (sGC) inhibitor NS2028 1a are synthesized. Treating 8-bromo-2H-benzo[b][1,4]oxazin-3(4H)-one oxime (6) with 1,1′-thiocarbonyldiimidazole (1.1 equiv) gave the carbamothioate 8-bromo-4H-[1,2,4]oxadiazolo[3,4-c][1,4]benzoxazine-1-thione (3a) in 83% yield. Alternatively reacting NS2028 1a with P2S5 (0.5 equiv) affords the carbamothioate 3a in 80% yield. Similar treatment of 8-aryl substituted NS2028 analogues 1b-d with P2S5 gave the carbamothioates 3b-d in 64-91% yields. Although quite stable, the carbamothioates 3a-d could be thermally isomerized in the presence of Cu (10 mol %) to afford the thiocarbamates 4a-d in high yields. Interestingly, in the case of carbamothioate 3a Pd and In metals also facilitated the isomerization. Furthermore, treatment of the thiocarbamates 4a-d with P2S5 (0.5 equiv) affords the carbamodithioates 5a-d in 72-89% yields. All new compounds are fully characterized including single crystal X-ray data for carbamothioate 3a and thiocarbamate 4a. Finally, a mechanism is proposed for the carbamothioate to thiocarbamate isomerization.  相似文献   

5.
The Pd-catalyzed reaction of [CpCo(S2C2(Ph)(Bpin))] (1, Bpin = 4,4,5,5-tetramethyl-1,3,2-dioxaboronate) with 1-iodonaphthalene or 2-bromothiophene gave the cross-coupling product [CpCo(S2C2(Ph)(Ar))] (Ar = 1-Np (4) or 2-Th (5)), although an early paper described the reaction of 1 with 3-bromopyridine or 9-bromoanthracene (Ar = 3-Py (2) or 9-Anth (3)). The boronation of the brominated precursor [CpCo(S2C2(p-C6H4Br)(H))] (7) with Bpin-H in the presence of Pd catalyst gave the expected boronated product [CpCo(S2C2(p-C6H4Bpin)(H))] (8) but also underwent an unexpected direct boronation on the dithiolene carbon to form [CpCo(S2C2(p-C6H4Br)(Bpin))] (9). The brominated complex 7 or [CpCo(S2C2(Ph)(p-C6H4Br))] (10) was synthesized by thermal reaction and the microwave-enhanced reaction relatively gave better yield with shorter reaction time than that of the conventional heating reaction. The cross-coupling reactions of the boronated or [CpCo(S2C2(Ph)(p-C6H4Bpin))] (11) with aryl halides successfully produced the corresponding cross-coupling products such as [CpCo(S2C2(p-C6H4Py)(H))] (12) or [CpCo(S2C2(p-C6H4Anth)(H))] (13) from 8 and [CpCo(S2C2(Ph)(p-C6H4Py))] (14) from 11. The structures of 7, 9, 11, 12, 13 and 14 were determined by X-ray diffraction studies. Electronic absorption maxima (λmax) due to dithiolene LMCT in dichloromethane solution can be modified in the range of 574-602 nm by a substituent effect on the dithiolene ring. Redox potentials obtained from CV measurement were also reported.  相似文献   

6.
The novel ruthenium dithiolene complexes [(arene)Ru{S2C2(COOMe)2}] (arene = C6H6 (1a), C6H4(Me)(iPr) (1b), C6Me6 (1c)) were synthesized. The equilibrium between complex 1a and the corresponding dimer [(C6H6)Ru{S2C2(COOMe)2}]2 (1a′) was confirmed in solution. The reaction of complex 1a with dimethyl- or diethylacetylene dicaboxylate gave the alkene-bridged adducts [(C6H6)Ru{S2C2(COOMe)2}{C2(COOR)2}] (R = Me (2a), Et (3a)) as [2 + 2] cycloaddition products formally. The reactions of complex 1a with diazo compounds also gave the alkylidene-bridged adducts [(C6H6)Ru{S2C2(COOMe)2}(CHR)] (R = H (4a), SiMe3 (5a), COOEt (6a)) as [2 + 1] cycloaddition products. The electrochemical behavior of complex 1a was investigated. The reductant of complex 1a was a stable species for several minutes. The oxidant of complex 1a was very unstable; the cation 1a+ formed was immediately converted to the corresponding cationic dimer 1a+. The cationic dimer 1a+ was stable for several minutes, and it was rapidly and quantitatively converted to the neutral complex 1a when it was reduced.  相似文献   

7.
The oxidative addition reactions of a bulky hexathioether containing a disulfide bond, TbtS(o-phen)S(o-phen)SS(o-phen)S(o-phen)STbt (1) (Tbt = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl, o-phen = o-phenylene), to a palladium(0) complex were studied. In the reaction of 1 with 3 molar amounts of [Pd(PPh3)4], a trinuclear palladium(II) complex, [Pd3{S(o-phen)S}2{(o-phen)STbt}2(PPh3)2] (2), was formed via three-step palladium insertion reaction including unusual C(aryl)-S bond cleavages. On the other hand, the reaction of 1 with an equimolar amount of [Pd(PPh3)4] afforded mononuclear palladium(II) complex having a pseudo-octahedral structure, [Pd{S(o-phen)S(o-phen)STbt}2] (3). The hexa-coordinated geometry for the palladium center in 3 was confirmed by the atoms in molecule (AIM) analysis, which revealed the presence of the bond critical points between the central Pd atom and the S atoms at the axial positions. In contrast to the bulky system, the reaction of Ph-substituted hexathioether, PhS(o-phen)S(o-phen)SS(o-phen)S(o-phen)SPh (4), with an equimolar amount of [Pd(PPh3)4] gave a palladium(II) complex having square-planar structure, [Pd{S(o-phen)S(o-phen)SPh}2] (5). Theoretical calculations revealed that there is no remarkable difference among the energies of isomers of [Pd{S(o-phen)SPh}2], 6a-syn, 6a-anti, 6b-syn, and 6b-anti. This result suggests that a reason for the preference of the trans-anti-conformation in 3 is the steric repulsion between the bulky Tbt groups, and that of the cis-syn-conformations in 5 and 6 is the intermolecular interactions.  相似文献   

8.
The reaction of trichlorosilane (1a) at 250 °C with cycloalkenes, such as cyclopentene (2a), cyclohexene (2b), cycloheptene (2c), and cyclooctene (2d), gave cycloalkyltrichlorosilanes [CnH2n−1SiCl3: n = 5 (3a), 6 (3b), 7 (3c), 8 (3d)] within 6 h in excellent yields (97-98%), but the similar reactions using methyldichlorosilane (1b) instead of 1a required a longer reaction time of 40 h and afforded cycloalkyl(methyl)dichlorosilanes [CnH2n−1SiMeCl2: n = 5 (3e), 6 (3f), 7 (3g), 8 (3h)] in 88-92% yields with 4-8% recovery of reactant 2. In large (2, 0.29 mol)-scale preparations, the reactions of 2a and 2b with 1a (0.58 mol) under the same condition gave 3a and 3b in 95% and 94% isolated yields, respectively. The relative reactivity of four hydrosilanes [HSiCl3−mMem: m = 0-3] in the reaction with 2a indicates that as the number of chlorine-substituent(s) on the silicon increases the rate of the reaction decreases in the following order: n = 3 > 2 > 1 ? 0. In the reaction with 1a, the relative reactivity of four cycloalkenes (ring size = 5-8) decreases in the following order: 2d > 2a > 2c > 2b. Meanwhile linear alkenes like 1-hexene undergo two reactions of self-isomerization and hydrosilylation with hydrosilane to give a mixture of the three isomers (1-, 2-, and 3-silylated hexanes). In this reaction, the reactivity of the terminal 1-hexene is higher than the internal 2- and 3-hexene. The redistribution of hydrosilane 1 and the polymerization of olefin 2 occurred rarely under the thermal reaction condition.  相似文献   

9.
The synthesis and the characterization of some new aluminum complexes with bidentate 2-pyrazol-1-yl-ethenolate ligands are described. 2-(3,5-Disubstituted pyrazol-1-yl)-1-phenylethanones, 1-PhC(O)CH2-3,5-R2C3HN2 (1a, R = Me; 1b, R = But), were prepared by solventless reaction of 3,5-dimethyl pyrazole or 3,5-di-tert-butyl pyrazole with PhC(O)CH2Br. Reaction of 1a or 1b with (R1 = Me, Et) yielded N,O-chelate alkylaluminum complexes (2a, R = R1 = Me; 2b, R = But, R1 = Me; 2c, R = Me, R1 = Et). Compound 1a was readily lithiated with LiBun in thf or toluene to give lithiated species 3. Treatment of 3 with 0.5 equiv of MeAlCl2 or AlCl3 yielded five-coordinated aluminum complexes [XAl(OC(Ph)CH{(3,5-Me2C3HN2)-1})2] (4, X = Me; 5, X = Cl). Reaction of 5 with an equiv of LiHBEt3 generated [Al(OC(Ph)CH{(3,5-Me2C3HN2)-1})3] (6). Complex 6 was also obtained by reaction of 3 with 1/3 equiv of AlCl3. Treatment of 5 with 2 equiv of AlMe3 yielded complex 2a, whereas with an equiv of AlMe3 afforded a mixture of 2a and [Me(Cl)AlOC(Ph)CH{(3,5-Me2C3HN2)-1}] (7). Compounds 1a, 1b, 2a-2c and 4-6 were characterized by elemental analyses, NMR and IR (for 1a and 1b) spectroscopy. The structures of complexes 2a and 5 were determined by single crystal X-ray diffraction techniques. Both 2a and 5 are monomeric in the solid state. The coordination geometries of the aluminum atoms are a distorted tetrahedron for 2a or a distorted trigonal bipyramid for 5.  相似文献   

10.
A series of salen-type zirconium complexes of the general formula LZrCl2 (L = N,N′-ethylenebis(salicylideneiminate), 3a; N,N′-ethylenebis(3,5-di-tert-butylsalicylideneiminate), 3b; N,N′-ethylenebis(5-methoxysalicylideneiminate), 3c; N,N′-ethylenebis(5-chlorosalicylideneiminate), 3d; N,N′-ethylenebis(5-nitrosalicylideneiminate), 3e; N,N′-o-phenylenebis(salicylideneiminate), 4a; N,N′-o-phenylenebis(3,5-di-tert-butylsalicylideneiminate), 4b; N,N′-o-phenylenebis(5-methoxysalicylideneiminate), 4c; N,N′-o-phenylenebis(5-chloro-salicylideneiminate), 4d) were prepared. The crystal structures of 6- and 7-coordinate zirconium complexes 4b and [4b · OCMe2] were determined by X-ray crystallography, which reveals that a salen-type zirconium complex possesses a labile coordination site on the Zr center with a relatively stable framework and that the coordination and the dissociation of O-donor molecules occur readily at this site. The catalytic properties of 3(a-e) and 4(a-d) were studied for ethylene oligomerization in combination with Et2AlCl as co-catalyst. Complex 3c featuring a methoxy-substituted salen ligand displayed higher activity than its analogous precursors having chloro and nitro groups as substituents. The catalytic reactions by 3(a-e) and 4(a-d) gave C4-C10 olefins and low-carbon linear α-olefins in good selectivity.  相似文献   

11.
The reaction pathway for the formation of the trimethylsiloxysilyllithium compounds (Me3SiO)RR′SiLi (2a: R = Et, 2b: R = iPr, 2c: R = 2,4,6-Me3C6H2 (Mes); 2a-c: R′ = Ph; 2d: R = R′ = Mes) starting from the conversion of the corresponding trimethylsiloxychlorosilanes (Me3SiO)RR′SiCl (1a-d) in the presence of excess lithium in a mixture of THF/diethyl ether/n-pentane at −110 °C was investigated.The trimethylsiloxychlorosilanes (Me3SiO)RPhSiCl (1a: R = Et, 1b: R = iPr, 1c: R = Mes) react with lithium to give initially the trimethylsiloxysilyllithium compounds (Me3SiO)RPhSiLi (2a-c). These siloxysilyllithiums 2 couple partially with more trimethylsiloxychlorosilanes 1 to produce the siloxydisilanes (Me3SiO)RPhSi-SiPhR(OSiMe3) (Ia-c), and they undergo bimolecular self-condensation affording the trimethylsiloxydisilanyllithium compounds (Me3SiO)RPhSi-RPhSiLi (3a-c). The siloxydisilanes I are cleaved by excess of lithium to give the trimethylsiloxysilyllithiums (Me3SiO)RPhSiLi (2). In the case of the two trimethylsiloxydisilanyllithiums (Me3SiO)RPhSi-RPhSiLi (3a: R = Et, 3b: R = iPr) a reaction with more trimethylsiloxychlorosilanes (Me3SiO)RPhSiCl (1a, 1b) takes place under formation of siloxytrisilanes (Me3SiO)RPhSi-RPhSi-SiPhR(OSiMe3) (IIa: R = Et, IIb: R = iPr) which are cleaved by lithium to yield the trimethylsiloxysilyllithiums (Me3SiO)RPhSiLi (2a, 2b) and the trimethylsiloxydisilanyllithiums (Me3SiO)RPhSi-RPhSiLi (3a, 3b). The dimesityl-trimethylsiloxy-silyllithium (Me3SiO)Mes2SiLi (2d) was obtained directly by reaction of the trimethylsiloxychlorosilane (Me3SiO)Mes2SiCl (1d) and lithium without formation of the siloxydisilane intermediate. Both silyllithium compounds 2 and 3 were trapped with HMe2SiCl giving the products (Me3SiO)RR′Si-SiMe2H and (Me3SiO)RPhSi-RPhSi-SiMe2H.  相似文献   

12.
The reactions of ketones 1a-o, nitromethane 2, and a stoichiometric amount of piperidine 3a or ethylenediamine 3b in the presence of mercaptan 6a in THF or CH3CN solution give high yields of β-nitrosulfides 7a-o. The latter can be oxidized by 8a (m-CPBA or m-CPBA/AcOH) at 0°C, 8b (H2O2/AcOH), or 8c (H2O2) at room temperature, thus generating β-nitroalkylsulfoxides 9a-o, which then undergo elimination to produce medium to high yields of 2,2-disubstituted-1-nitroalkenes 5a-o, when refluxed in a solution of ClCH2CH2Cl (1,2-dichloroethane). After preparation from 1a-o, 2, 3, and 6a, 7a-o were oxidized with 8a, 8b, or 8c in a mixture of CH3CN and ClCH2CH2Cl to generate β-nitrosulfoxides 9a-o, which then underwent elimination under refluxing under one-pot conditions. Compounds 14 and 15g were also prepared using 13, 2, 3b, and 6, in a similar manner.  相似文献   

13.
Fluorotitanates (LH)2[TiF6nH2O (1: R = pyridine, n = 1, 2: R = 2-picoline, n = 2, 3: R = 2,6-lutidine, n = 0, 4: R = 2,4,6-collidine, n = 0) and (LH)[TiF5(H2O)] (3a: L = 2,6-lutidine) have been synthesized by the reaction of pyridine or corresponding methyl substituted pyridines and titanium dioxide dissolved in hydrofluoric acid. The crystal structures of ionic compounds 1, 2, 3, 3a and 4 have been determined by single-crystal X-ray diffraction analysis. The hydrogen bonding led to the formation of discrete (LH)2[TiF6] units (4), chains (1-3), and layers (3a). The additional π-π interactions present in 1, 2, and 4 results in chain structures of 1 and 4 and in a layer structure of 2. The [TiF6]2− and [TiF5(H2O)] anions were observed by 19F NMR spectroscopy in aqueous solutions of 1, 2, 3, 3a and 4.  相似文献   

14.
[MBr(CO)3{κ2(N,O)-pyca}] [M = Mn(1a), Re(1b), pyca = pyridine-2-carboxaldehyde] and [MoCl(η3-C3H4Me-2)(CO)2{κ2(N,O)-pyca}] (1c) react with aminoacid β-alanine to give the corresponding iminopyridine complexes 2a-2c. The same method affords the iminopyridine derivatives from γ-aminobutyric acid (GABA) (3a-3c) and 3-aminobenzoic acid (4a-4c). For complexes 2a-2c, 3a, 3c and 4a, the solid state structures have been determined by X-ray crystallography, revealing interesting differences in their hydrogen-bonding patterns in solid state.  相似文献   

15.
The reactions of the trimethylsiloxychlorosilanes (Me3SiO)RR′SiCl (1a-h: R′ = Ph, 1a: R = H, 1b: R = Me, 1c: R = Et, 1d: R = iPr, 1e: R = tBu, 1f: R = Ph, 1g: R = 2,4,6-Me3C6H2 (Mes), 1h: R = 2,4,6-(Me2CH)3C6H2 (Tip); 1i: R = R′ = Mes) with lithium metal in tetrahydrofuran (THF) at −78 °C and in a mixture of THF/diethyl ether/n-pentane in a volume ratio 4:1:1 at −110 °C lead to mixtures of numerous compounds. Dependent on the substituents silyllithium derivatives (Me3SiO)RR′SiLi (2b-i), Me3SiO(RR′Si)2Li (3a-g), Me3SiRR′SiLi (4a-h), (LiO)RR′SiLi (12e, 12g-i), trisiloxanes (Me3SiO)2SiRR′ (5a-i) and trimethylsiloxydisilanes (6f, 6h, 6i) are formed. All silyllithium compounds were trapped with Me3SiCl or HMe2SiCl resulting in the following products: (Me3SiO)RR′SiSiMe2R″ (6b-i: R″ = Me, 7c-i: R″ = H), Me3SiO(RR′Si)2SiMe2R″ (8a-g: R″ = Me, 9a-g: R″ = H), Me3SiRR′SiSiMe2R″ (10a-h: R″ = Me, 11a-h: R″ = H) and (HMe2SiO)RR′SiSiMe2H (13e, 13g-i). The stability of trimethylsiloxysilyllithiums 2 depends on the substituents and on the temperature. (Me3SiO)Mes2SiLi (2i) is the most stable compound due to the high steric shielding of the silicon centre. The trimethylsiloxysilyllithiums 2a-g undergo partially self-condensation to afford the corresponding trimethylsiloxydisilanyllithiums Me3SiO(RR′Si)2Li (3a-g). (Me3)Si-O bond cleavage was observed for 2e and 2g-i. The relatively stable trimethylsiloxysilyllithiums 2f, 2g and 2i react with n-butyllithium under nucleophilic butylation to give the n-butyl-substituted silyllithiums nBuRR′SiLi (15g, 15f, 15i), which were trapped with Me3SiCl. By reaction of 2g and 2i with 2,3-dimethylbuta-1,3-diene the corresponding 1,1-diarylsilacyclopentenes 17g and 17i are obtained.X-ray studies of 17g revealed a folded silacyclopentene ring with the silicon atom located 0.5 Å above the mean plane formed by the four carbon ring atoms.  相似文献   

16.
The preparation and characterization are described for four ruthenium(II) complexes containing hemilabile phosphine-ether ligand o-(diphenylphosphino)anisole (Ph2PC6H4OMe-o) and/or bidentate ligand diphenylphosphino-phenolate ([Ph2PC6H4O-o]) Ru(RCN)22-Ph2PC6H4O-o)2 (1a: R = Me; 1b: R = Et) and [Ru(RCN)22-Ph2PC6H4O-o)(κ2-Ph2PC6H4OMe-o)](PF6) (2a: R = Me; 2b: R = Et). The ruthenium(II) phosphine-ether complexes undergo mild methyl-oxygen bond cleavage. Two different kinds reaction mechanism are proposed to describe the methyl-oxygen bond cleavage, one involving attack of anionic nucleophiles and another involving the phosphine. The new reactions define novel routes to phosphine-phenolate complexes. The structures of complexes 1a, 1b and 2a were confirmed by X-ray crystallography.  相似文献   

17.
Treatment of the thiosemicarbazones 2-XC6H4C(Me)NN(H)C(S)NHR (R = Me, X = F, a; R = Et, X = F, b; R = Me, X = Cl, c; R = Et, X = Br, d) with potassium tetrachloropalladate(II) in ethanol, lithium tetrachloropalladate(II) in methanol or palladium(II) acetate in acetic acid, as appropriate, gave the tetranuclear cyclometallated complexes [Pd{2-XC6H3C(Me)NNC(S)NHR}]4 (1a-1d). Reaction of 1a-1d with the diphosphines Ph2PCH2PPh2 (dppm), Ph2P(CH2)2PPh2 (dppe), Ph2P(CH2)3PPh2 (dppp) or trans-Ph2PCHCHPPh2 (trans-dpe) in 1:2 molar ratio gave the dinuclear cyclometallated complexes [{Pd[2-XC6H3C(Me)NNC(S)-NHR]}2(μ-diphosphine-P,P)] (2a-5a, 3b, 3d, 4c, 5c). Reaction of 1a, 1b with the short-bite or long-bite diphosphines, dppm or cis-dpe, in a 1:4 molar ratio gave the mononuclear cyclometallated complexes [Pd{2-XC6H3C(Me)NNC(S)NHR}(diphosphine-P)] (6a, 6b, 7a). The molecular structure of ligand a and of complexes 1a, 3d, 5a, 5c, 6a, 6b and 7a have been determined by X-ray diffraction analysis. The structure of complex 7a shows that the long-bite cis-bis(diphenylphosphino)ethene phosphine appears as monodentate with an uncoordinated phosphorus donor atom.  相似文献   

18.
The new mononuclear palladium(II) and platinum(II) [M(p-SC6F4(CF3))2(dppe)] complexes M = Pd 1a, Pt 2a; [M(o-SC6H4(CF3))2(dppe)] M = Pd 1d, Pt 2d as well as the previously known [M(SC6F5)2(dppe)] M = Pd 1b, Pt 2b and [M(p-SC6HF4)2(dppe)] M = Pd 1c, Pt 2c, have been used as metalloligands for the preparation of the heteroleptic bimetallic complexes [M2(μ-SRf)2(dppe)2](SO3CF3)2 M = Pd, Rf = p-C6F4(CF3) 3a, C6F53b, p-C6HF43c, o-C6H4(CF3) 3d; M = Pt, Rf = p-C6F4(CF3) 4a, C6F54b, p-C6HF44c and o-C6H4(CF3) 4d. Variable temperature 19F NMR experiments show that the fluorothiolate bridged bimetallic compounds are fluxional in solution whereas mononuclear complexes are not. The solid state X-ray diffraction structures of [Pd(p-SC6HF4)2(dppe)] (1c), [Pt(SC6F5)2(dppe)] (2b) and [Pt(o-SC6H4(CF3))2(dppe)] (2d) show square-planar coordination around the metal centers. The solid state molecular structure of the compound [Pt2(μ-o-SC6H4(CF3))2(dppe)2](SO3CF3)2 (4d), exhibit a planar [Pt2(μ-S)2] ring with the sulfur substituents in an anti configuration.  相似文献   

19.
Ph2SiCl2 and PhMeSiCl2 react with Li2E (E = S, Se, Te) under formation of trimeric diorganosilicon chalcogenides (PhRSiE)3 (R = Ph: 1a-3a, R = Me: cis/trans-4a (E = S), cis/trans-5a (E = Se)). In case of E = S, Se dimeric four-membered ring compounds (PhRSiE)2 (R = Ph: 1b-2b, R = Me: cis/trans-4b (E = S), cis/trans-5b (E = Se)) have been observed as by-products. 1a-5b have been characterized by multinuclear NMR spectroscopy (1H, 13C, 29Si, 77Se, 125Te). Four- and six-membered ring compounds differ significantly in 29Si and 77Se chemical shifts as well as in the value of 1JSiSe.The molecular structures of 2a, 3a and trans-5a reported in this paper are the first examples of compounds with unfused six-membered rings Si3E3 (E = Se, Te). The Si3E3 rings adopt twisted boat conformations. The crystal structure of 3a reveals an intermolecular Te-Te contact of 3.858 Å which yields a dimerization in the solid state.  相似文献   

20.
2-Phenylaniline reacted with Pd(OAc)2 in toluene at room temperature for 24 h in a one-to-one molar ratio and with the system PdCl2, NaCl and NaOAc in a 1 (2-phenylaniline):1 (PdCl2):2 (NaCl):1 (NaOAc) molar ratio in methanol at room temperature for one week to give the dinuclear cyclopalladated compounds (μ-X)2[Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}]2 [1a (X = OAc) and 1b (X = Cl)] in high yield. Moreover, the reaction between 2-phenylaniline and Pd(OAc)2 in one-to-one molar ratio in acid acetic at 60 °C for 4 h, followed by a metathesis reaction with LiBr, allowed isolation of the dinuclear cyclopalladated compound (μ-Br)2[Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}]2 (1c) in moderate yield. A parallel treatment, but using monodeuterated acetic acid (DOAc) as solvent in the cyclopalladation reaction, allowed isolation of a mixture of compounds 1c, 1cd1 [Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4](μ-Br)2[Pd{κ2-N2′,C1-2-(2′-NH2C6H4)-3-d-C6H3] and 1cd2 (μ-Br)2[Pd{κ2-N2′,C1-2-(2′-NH2C6H4)-3-d-C6H3}]2 in moderate yield and with a deuterium content of ca. 60%. 1a and 1b reacted with pyridine and PPh3 affording the mononuclear cyclopalladated compounds [Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}(X)(L)] [2a (X = OAc, L = py), 2b (X = Cl, L = py), 3a (X = OAc, L = PPh3) and 3b (X = Cl, L = PPh3)] in a yield from moderate to high. Furthermore, 1a reacted with Na(acac) · H2O to give the mononuclear cyclopalladated compound 4 [Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}(acac)] in moderate yield. 1H NMR studies in CDCl3 solution of 2a, 2b, 3a, 3b and 4 showed that 2a and 3a presented an intramolecular hydrogen bond between the acetato ligand and the amino group, and were involved in a dynamic equilibrium with water present in the CDCl3 solvent; and that the enantiomeric molecules of 2b and 4 were in a fast exchange at room temperature, while they were in a slow exchange for 2a, 3a and 3b. The X-ray crystal structures of 3b and 4 were determined. 3b crystallized in the triclinic space group with a = 9.9170(10), b = 10.4750(10), c = 12.0890(10) Å, α = 98.610(10)°, β = 94.034(10)° and γ = 99.000(10)° and 4 in the monoclinic space group P21/a with a = 11.5900(10), b = 11.2730(10), c = 12.2150(10) Å, α = 90°, β = 107.6560(10)° and γ = 90°.  相似文献   

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