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1.
Novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF 2) fluorescent dyes (BOPYPYs) were obtained by reaction of pyrrole-2-carboxaldehyde with 1-(pyrazin-2-yl)hydrazine in the presence of Et 3N-BF 3·Et 2O for the first time. The absorption maxima of pyrazine-fused BOPYPY are obviously bathochromic shifts, in contrast to those of the reported BOPPY, indicating that the discrepant substitute groups between pyridine and pyrazine result in the remarkable wavelength difference. The new series of BOPYPYs possess high molar extinction coefficients, high fluorescence quantum yields, and larger Stokes shifts. A Knoevenagel reaction of BOPYPY with 4-dimethylaminobenzaldehyde smoothly produced the dye with the extension of π-conjugation. Dimethylamino-containing BOPYPY as a pH-responsive fluorescent sensor could detect pH value. 相似文献
2.
A series of isomalononitrile dithiolato palladium complexes, (PPh 3) 2Pd(1-mnt) (1), [P(OPh) 3] 2Pd( i-mnt) (2), (PPh 3)(py)Pd( i-mnt)·CH 3CN (4), (Et 4N) 2Pd( i-mnt) 2 (4) and (Ph 4As) 2Pd( i-mnt) 2 (5) were synthesized and characterized by elemental analysis and IR spectroscopy. The reaction between (Et 4N) 2Pd( i-mnt) 2 (4) and (Et 4N) 2WS 4 gave a mixed metal cluster (Et 4N) 2WS 4Pd( i-mnt) (6). The crystallographically determined structures of 1 and 6 are reported. 相似文献
3.
The new terminal phosphinidene complex [Cp 2Zr=PDmp(PMe 3)] (Dmp=2,6-Mes 2C 6H 3; 1) was prepared in 81% yield by the reaction of [Li(Et 2O)][P(H)Dmp] with [Cp 2Zr(Me)Cl] in the presence of excess PMe 3. Compound 1 reacts with Ph 2PCl to produce selectively the sterically congested triphosphane DmpP(PPh 2) 2 (2) and [Cp 2ZrCl 2] in high yields. The structure of 2 obtained by X-ray diffraction analysis of a single crystal reveals phosphorus–phosphorus bond lengths of 2.251(2) and 2.234(2) Å and a PPP bond angle of 105.46(6)°. 相似文献
4.
合成并表征了[BMIm]Cl-1.8AlCl3-0.5CuCl、[Et3NH]Cl-1.8AlCl3/CuAlCl4等离子液体,考察了含Cu离子液体等酸性催化剂中的异丁烷/丁烯烷基化反应,研究了Cu对离子液体烷基化选择性的影响。结果表明,Cu的引入对离子液体酸性的影响较小,不是反应选择性提高的主要原因,而烷基化过程中CuAlCl5-/CuAlCl4等配合物的存在,以及它们对2-丁烯的络合吸附是改善离子液体催化选择性的关键因素。相同反应条件下,[Et3NH]Cl-1.8AlCl3/CuAlCl4、[BMIm]Cl-1.8AlCl3/CuAlCl4等催化剂的三甲基戊烷选择性最高可达87.5%(质量分数),产物辛烷值100.5,明显优于硫酸、常规氯铝酸离子液体和复合离子液体等烷基化汽油辛烷值。 相似文献
5.
The reactions of the diruthenium carbonyl complexes [Ru 2(μ-dppm) 2(CO) 4(μ,η 2-O 2CMe)]X (X=BF 4− (1a) or PF 6− (1b)) with neutral or anionic bidentate ligands (L,L) afford a series of the diruthenium bridging carbonyl complexes [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-(L,L)) 2]X n ((L,L)=acetate (O 2CMe), 2,2′-bipyridine (bpy), acetylacetonate (acac), 8-quinolinolate (quin); n=0, 1, 2). Apparently with coordination of the bidentate ligands, the bound acetate ligand of [Ru 2(μ-dppm) 2(CO) 4(μ,η 2-O 2CMe)] + either migrates within the same complex or into a different one, or is simply replaced. The reaction of [Ru 2(μ-dppm) 2(CO) 4(μ,η 2-O 2CMe)] + (1) with 2,2′-bipyridine produces [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-O 2CMe) 2] (2), [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-O 2CMe)(η 2-bpy)] + (3), and [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-bpy) 2] 2+ (4). Alternatively compound 2 can be prepared from the reaction of 1a with MeCO 2H–Et 3N, while compound 4 can be obtained from the reaction of 3 with bpy. The reaction of 1b with acetylacetone–Et 3N produces [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-O 2CMe)(η 2-acac)] (5) and [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-acac) 2] (6). Compound 2 can also react with acetylacetone–Et 3N to produce 6. Surprisingly [Ru 2(μ-dppm) 2(μ-CO) 2(η 2-quin) 2] (7) was obtained stereospecifically as the only one product from the reaction of 1b with 8-quinolinol–Et 3N. The structure of 7 has been established by X-ray crystallography and found to adopt a cis geometry. Further, the stereospecific reaction is probably caused by the second-sphere π–π face-to-face stacking interactions between the phenyl rings of dppm and the electron-deficient six-membered ring moiety of the bound quinolinate (i.e. the N-included six-membered ring) in 7. The presence of such interactions is indeed supported by an observed charge-transfer band in a UV–vis spectrum. 相似文献
6.
Dehydrocoupling reactions of primary amines RNH 2 with PhSiH 3 were catalyzed by [(Et 2N) 3U][BPh 4] to give the corresponding aminosilanes PhSiH 3−n(NHR) n ( n=1–3), the relative yields of the products were found to be dependent on the experimental conditions and on the nature of R. For a primary silane (PhSiH 3), the reactivity of RNH 2 follows the order primary>secondary>tertiary. Similar dehydrocoupling reactions using secondary amines with secondary silanes were found to be less reactive. Homodehydrocoupling of the silane was found not to be a competing reaction at room temperature. The hydride [(RNH) 2UH][BPh 4], which is plausibly formed in the reaction of [(RNH) 3U][BPh 4] with PhSiH 3 is a likely intermediate in the catalytic cycle. 相似文献
7.
通过由Fe 3(CO) 12、RSH和Et 3N所形成的[(μ-CO)(μ-RS)Fe 2(CO) 6]Et 3NH于室温下分别与对或间苯二甲酰氯的原位反应,首次合成6个结构新颖的苯二甲酰基桥联铁硫配合物[(μ-RS)·Fe 2(CO) 6] 2(μ-p-OCC 6H 4CO-p-μ)(R=Et,n-Bu,t-Bu)以及[(μ-RS)Fe 2(CO) 6] 2(μ-m-OCC 6H 4CO-m-μ)(R=n-Pr,n-Bu,t-Bu).经元素分析、IR光谱及 1HNMR表征了它们的结构,并讨论了产物的生成过程.此外,还提出了合成对苯二甲酰氯的一种新方法. 相似文献
8.
Reactions between thiomolybdate or thiotungstate [Et 4N] 2[MS 4] (M = Mo, W) and CuSBu t led to the formation of two novel Mo(W)/Cu/S clusters [Et 4N] 4[{MS 4Cu 2(μ-SBu t)} 4] (1, M = Mo; 2, M = W). Single-crystal X-ray diffraction studies reveal that 2 is the first example of a molecular square containing CuS 2WS 2Cu building blocks. The reactions of [Et 4N] 2[MS 4] with CuCl followed by the addition of K 2SSS (SSS = 1,3,4-thiadiazole-2,5-dithiolate) yielded novel polymers {[Et 4N] 2[MS 4Cu 2(SSS)]} n (3, M = Mo; 4, M = W). Crystal structure determination shows that the CuS 2WS 2Cu building blocks in the anion of 4 are bridged by SSS 2− ligands to produce a helical chain running down the crystallographic b axis. 相似文献
9.
Soluble homogeneous organophosphorus—nickel complexes have been used to detoxify polychlorinated biphenyls (PCBs) by catalyzed hydrodechlorination using NaBH 2(OCH 2CH 2OCH 3) 2 as the hydrogen source. The reactions appear to proceed by NiL 3 oxidative addition into C---Cl bonds followed by hydrogenolysis of the metal---carbon bond. In model experiments with decachlorobiphenyl, the cone angle of the organophosphorus ligand L was shown to be a key factor controlling the magnitude and position of chlorine displacement. Hence, ligands leading to para displacement (e.g. ( o-MeC 6H 4O) 3P), meta—para displacement (e.g. (EtO) 3P and (PhO) 3P), and ortho—meta—para displacement (e.g. Me 3P and Et 3P) were found. Significantly, the highly toxic, coplanar dioxin precursor 3,3′,4,4′-tetrachlorobiphenyl, a meta—para chlorine-substituted congener, was dechlorinated quantitatively with the Et 3P catalyst system. Evidence for the presence of organonickel intermediates in the reaction mixtures was obtained by mass spectroscopic and X-ray diffraction studies. Of particular interest is the isolation of square planar complexes p-C 6Cl 5C 6Cl 4Ni(PEt 3) 2Cl from the reaction of decachlorobiphenyl with NaBH 2(OCH 2CH 2OCH 3) 2—(Et 3P) 2NiCl 2 as the catalyst precursor and m-C 6Cl 5C 6Cl 4Ni(PEt 3) 2Cl from decachlorobiphenyl—Ni(1,5-C 8H 12) 2—PEt 3 at room temperature. All are oxidative addition intermediates and precursors for decachlorobiphenyl hydrodechlorination. 相似文献
10.
The composition of (C 6Me 6)TiAl 2Cl 8−xEt x complexes in (C 6Me 6)TiAl 2Cl 8 + n Et 3Al ( n = 0.5-6) systems was studied by UV-Vis spectroscopy and the X-ray crystal structure of one of them, (η 6-C 6Me 6)Ti[(μ-Cl) 2(AlClEt)] 2 (IIa-2), has been determined. The complex crystallizes in the orthorhombic space group Pna2 1 with Z = 4 and lattice parameters a 15.634(3), b 11.355(2), c 14.417(2) Å. The ethyl groups of IIa-2 reside in outer positions of aluminate ligands farther away from the C 6Me 6 ligand. The other part of the complex does not differ remarkably from structures of other (arene)Ti II complexes. Negligible activity of (C 6Me 6)TiAl 2Cl 8 towards the butadiene cyclotrimerization is considerably increased by addition of 2.5–3.0 equivalents of Et 3Al. As follows from UV-Vis spectra, such systems contain mainly the (C 6Me 6)TiAl 2Cl 5Et 3 complex. It is suggested that the introduction of three Et substituents destabilizes the Ti-(η 6-C 6Me 6) bond so that the replacement of hexamethylbenzene by butadiene in the first step of a catalytic cycle becomes more feasible. 相似文献
11.
The presence of BF 3·Et 2O in reactions of R 2Cu(CN)Li 2 and R T(2-thienyl)Cu(CN)Li 2 with epoxides and ,β-unsaturated ketones leads to dramatic enhancements in reaction rates and/or product yields relative to those observed in the absence of this lewis Acid. 相似文献
12.
Lewis acidic ionic liquids were used to catalyze the reaction of epoxypropane with POCl 3.Considering the lower cost and catalytic activities,we concluded that[Et 3NH]Cl/AlCl 3 was the most attractive ionic liquid from an economical point of view.But it would be easily inactivated because of sensitive to water and air.Moreover,it could not be reused easily because of difficulty recovery in the reaction.However,supporting[Et 3NH]Cl/AlCl 3 catalyst could resolve above problems.Supporting[Et 3NH]Cl/ AlCl 3 catalyst could be separated by filter easily and reused 5 times in 98%yield.Furthermore,the catalyst was applicable to other epoxy ether cleaving reactions. 相似文献
13.
The thermally (decomp. temp. 300°C) and completely air stable, novel coordination polymers [(Me 3Sn IV) 2(Me 3Sb V)M II(CN) 6] ∞ with M = Fe and Ru can be prepared by co-precipitation from aqueous solutions of Me 3SnCl, Me 3SbBr 2 and K 4[(M(CN) 6], or, alternatively, by the ion-exchange-like reaction of the polymers [A(Me 3Sn) 3M(CN) 6] ∞ (A + = Et 4N +, Cp 2Co +, Me 3Sn + etc.) with Me 3SbBr 2. IR-spectroscopic findings suggest a statistical distribution of quasi-octahedral M(CN-Sn··) 6-x(CNSb ··) x building blocks (with x = 0–6) within a three-dimensional network. 相似文献
14.
The synthesis of allylic sila (and germa) cyclopentenes containing an Et 3M (M = Si, Ge) group in vinylic position is described. 1-Germacyclopent-3-enes 3-silylated (IIIa) and 3-germylated (IIIb) result from 1,4-cycloaddition of GeI 2 to the corresponding 2-metallated 1,3-dienes (II). 3-Metallated 1-silacyclopent-3-enes (IIIc–IIIf) are obtained by two methods. One involves the reaction of dienes II with Me 2SiCl 2 and Mg, leading to compounds IIIc (M = Si) and IIId (M = Ge). The other method corresponds to the trichlorosilylation (HSiCl 3, Et 3N, ε Cu 2Cl 2) of dichlorinated compounds I resulting from cis-addition of Et 3MH to cis-1,4-dichlorobutyne. From the two trichlorosilylated derivatives IV and V, formed in SN2 and SN2′ reactions, only the 1-trichlorosilyl 2-triethylsilyl (and germyl) 4-chlorobut-2-enes (IV) give, in the presence of magnesium, the 1,1-dichloro 3-triethylsilyl (and germyl) 1-silacyclopent-3-enes (IIIe and IIIf). AbstractNous décrivons la synthèse de sila (et germa) cyclopentènes allyliques (III) renfermant le groupe Et3M (M = Si, Ge) en position vinylique. Les 1-germacyclopent-3-ènes 3-silylés (IIIa) et 3-germylés (IIIb) sont obtenus par réaction de cycloaddition-1,4 de GeI2 sur les diènes 2-métallés (II) correspondants. Les 1-silacyclopent-3-ènes métallés (IIIc–IIIf) sont préparés selon deux méthodes. L'une, mettant en jeu les diènes II et le couple Me2SiCl2 Mg, conduit aux cycles IIIc (M = Si) et IIId (M = Ge). L'autre méthode consiste à effectuer la réaction de trichlorosilylation (HSiCl3, Et3N, ε Cu2Cl2) des dérivés dichlorés I qui résultent de la cis-addition de Et3MH au cis-1,4-dichlorobutyne. Des deux dérivés trichlorosilylés IV et V formés à l'issue des réactions SN2 et SN2′, seuls les 1-trichlorosilyl 2-triéthylsilyl (et germyl) 4-chlorobut-2-ènes (IV) conduisent, après cyclisation par le magnésium, aux 1,1-dichloro-3-triéthylsilyl (et germyl) 1-silacyclopent-3-enes (IIIe et IIIf). 相似文献
15.
[W 3Se 7(S 2P(OEt) 2) 3]Br was prepared by reacting (Et 4N) 2W 3Se 7Br 6 with KS 2P (OEt) 2 in CH 3CN and its crystal structure determined. In the [W 3(μ 3-Se)(μ 2-Se 2) 3] 4+ core the W---W bond length is 2.755(5)-2.764(6) Å and the Se---Se bond length is 2.32(1)- 2.34(4) Å. 相似文献
16.
Mixed ketoiminate/ketoimine/pentamethylcyclopentadienyl (Cp*) complex of zirconium, [(η 5-Cp*){CH 3C(O)CHC(NHR)CH 3}{CH 3C(O)CHC(NR)CH 3}ZrCl 2] (R=4 -CF 3Ph) (3) has been prepared in high yield by the reaction of one equivalent of 4-CF 3-phenyl-β-ketoimine (1a) and one equivalent of lithium 4-CF 3-phenyl-β-ketoiminate (2a) with one equivalent of Cp*ZrCl 3 in Et 2O. Bis(ketoiminate)zirconium dichloride complexes, 4 and 6, have been also prepared in high yield by the reaction of amine elimination of ketoimine ligands, respectively 1a and 1b, with Zr(NMe 2) 4 and followed by chlorination reaction with TMSCl. The X-ray crystallography reveals that the compound 3 is based on distorted octahedral geometry containing a ketoimine and a ketoiminate. The ketoiminate ligand coordinates to the zirconium as a bidentate ligand, leaving the metal center coordinatively unsaturated and thus leading to an additional binding of a ketoimine ligand to the metal to stabilize the complex 3. The zirconium complexes 3, 4 and 6 provide the moderate activity for the polymerization of ethylene in the presence of MMAO cocatalyst. Low molecular weight and high density polyethylene was obtained. 相似文献
17.
Arenediazonium tetrafluoroborates (ArN 2BF 4 where Ar = X-C 6H 4; X = H, 2-Me, 3-Me, 4-Me, 4-MeO, 4-MeCO, 4-EtOCO, 2-Ph, 2-Cl, 3-Cl, 4-Cl, 4-Br, 4-I, 3-NO 2 and 4-NO 2) were easily converted to aromatic aldehydes (ArCHO) in good yields through the palladium-catalyzed reaction with CO and Et 3SiH or polymethylhydrosiloxane (PMHS) at room temperature. 相似文献
18.
When the mixture of CpTiCl_3-KI is used, many acetals and ketals, which are difficuitly deprotected with CpTiCl_3 alone, can be easily converted to the corresponding carbonyl compounds in high yield at 30℃ in Et_2O. 相似文献
19.
The new organosilicon bromides (Me 3Si) 2(ZMe 2Si)CSiMe 2Br with Z=PhO or MeS have been prepared and new spectroscopic data obtained for the previously reported compounds with Z=H, F, Br, Me, Ph, MeO or PhS. Competitions between pairs of bromides for a deficiency of AgBF 4 in Et 2O, with the determination of the ratio of the fluoride products by 19F-NMR spectroscopy, have led to the following approximate relative reactivities of the bromides and so to the relative abilities of the γ-Z groups to provide anchimeric assistance to the leaving of Br − in this reaction: Me, 1; Ph, 40; PhO, 3400; PhS, 5000; MeS, 7000; MeO, 54 000. In methanolysis in CH 2Cl 2, (Me 3Si) 2(MeOMe 2Si)CSiMe 2Cl has been found to be roughly 120 times as reactive as (Me 3Si) 2(PhOMe 2Si)CSiMe 2Cl. Combination of the results with previously available information suggests the following approximate order of ability of γ-groups Z to provide anchimeric assistance in reactions at the Si---X bonds in compounds (Me 3Si) 2(ZMe 2Si)CSiMe 2X: OCOMe>OMe>OCOCF 3>MeS>PhS, PhO>N 3, Cl>NCS>Ph>CH=CH 2>Me. 相似文献
20.
Treatment of (η 5-C 5Me 5)RuCl 2(PR 3) (1) with LiAlH 4 in diethyl ether gives the ruthenium(II) tetrahydroaluminate complexes, (η 5-C 5Me 5)Ru(AlH 4)(PR 3) (2) (R 3 = Me 3, Et 3, iPr 3, Ph 2Me, Ph 3), which can be quantitatively converted to the trihydriodurthenium(IV) complexes (η 5-C 5Me 5)RuH 3(PR 3) (4), via protonolysis either by reaction with ethanol or by filtration through alumina. Low-temperature 1H NMR studies suggest the fluxionality of complexes 2 in solution at ambient temperature. 相似文献
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