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1.
The racemic carbonate complex [Co(en)2O2CO]+ Cl? (en=1,2‐ethylenediamine) and (S)‐[H3NCH((CH2)nNHMe2)CH2NH3]3+ 3 Cl? (n=1–4) react (water, charcoal, 100 °C) to give [Co(en)2((S)‐H2NCH((CH2)nNHMe2)CH2NH2)]4+ 4 Cl? ( 3 a – d H4+ 4 Cl?) as a mixture of Λ/Δ diastereomers that separate on chiral‐phase Sephadex columns. These are treated with NaOH/Na+ BArf? (BArf=B(3,5‐C6H3(CF3)2)4) to give lipophilic Λ‐ and Δ‐ 3 a–d 3+ 3 BArf?, which are screened as catalysts (10 mol %) for additions of dialkyl malonates to nitroalkenes. Optimal results are obtained with Λ‐ 3 c 3+ 3 BArf? (CH2Cl2, ?35 °C; 98–82 % yields and 99–93 % ee for six β‐arylnitroethenes). The monofunctional catalysts Λ‐ and Δ‐[Co(en)3]3+ 3 BArf? give enantioselectivities of <10 % ee with equal loadings of Et3N. The crystal structure of Δ‐ 3 a H4+ 4 Cl? provides a starting point for speculation regarding transition‐state assemblies.  相似文献   

2.
The complex formation of PdII with tris[2-(dimethylamino)ethyl]amine (N(CH2CH2N(CH3)2)3, Me6tren) was investigated at 25° and ionic strength I = 1, using UV/VIS, potentiometric, and NMR measurements. Chloride, bromide, and thiocyanate were used as auxiliary ligands. The stability constant of [Pd(Me6tren)]2+ in various ionic media was obtained: log β([Pd(Me6tren)] = 30.5 (I = 1(NaCl)) and 30.8 (I = 1(NaBr)), as well as the formation constants of the mixed complexes [Pd(HMe6tren)X]2+ from [Pd(HMe6tren)(H2O)]3+:log K = 3.50 = Cl?) and 3.64 (X? = Br?) and [Pd(Me6tren)X]+ from [Pd(Me6tren)(H2O)]2+: log K = 2.6 (X? = Cl?), 2.8(Br?) and 5.57 (SCN?) at I = 1 (NaClO3). The above data, as well as the NMR measurements do not provide any evidence for the penta-coordination of PdII, proposed in some papers.  相似文献   

3.
The new complexes [(η3-Me2CCMeCH2)Pd{η2-Ph2P(S)CHP(S)Ph2] (1), [(η3-Me2CCMeCH2)Pd{η2-OC(CF3) CHCO(C4H3S)}] (2) and [(η3-CH2CMeCH2)Pd{η2-OC(CF3)CHCO(C4H3S)}] (3) have been synthesized by reacting [(η3-allyl)Pd(μ-Cl)]2 with Ph2P(S)CH2P(S)Ph2 and OC(CF3)CH2CO(C4H3S) in the presence of base. All have been characterized by elemental analysis, FT-IR, 1H-n.m.r and FAB-mass spectroscopy. Spectroscopic studies suggest that both ligands are bidentate, forming six-membered Pd-S-P-C-P-S and Pd-O-C-C-C-O palladacycles, the η3-allyl group completing the coordination sphere.  相似文献   

4.
The five-coordinate trigonal-bipyramidal palladium(II) and platinum(II) complexes with sulfur-coordinated glutathione at the axial position, [Pd(gluta)(pp3)](BF4) and [Pt(gluta)(pp3)](PF6) (gluta = glutathionate, pp3 = tris[2-(diphenylphosphino)ethyl]phosphine), were prepared and characterized by 31P NMR spectroscopy. The dimeric square-planar platinum(II) complex [Pt(pp3)]2(PF6)4 gave the monomeric five-coordinate solvated complex, [Pt(pp3)(CH3CN)]2+, in acetonitrile. Extraction experiments for amino acids from the aqueous solution to the chloroform layer were carried out by using [Pd(pp3)(CH3CN)]2+, [Pt(pp3)(CH3CN)]2+, and [Pd(p3)(CH3CN)]2+ (p3 = bis[2-(diphenylphosphino)ethyl]phenylphosphine) as extractants. High selectivity for the thiolate sulfur atom in l-cysteinate was observed at the solvated coordination site in [Pd(pp3)(CH3CN)]2+. The selectivity was applied to extraction of l-cysteinate from a mixture of some amino acids and, further, the reduced form of glutathionate from a mixture of the reduced and oxidized forms of glutathione.  相似文献   

5.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H3CH?C(CN)2 (where R is 2,3-(CH3O)2, 2,4-(CH3O)2, 2,5-(CH3O)2, 2,6-(CH3O)2, 3,4-(CH3O)2, and 3,5-(CH3O)2 and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 2,6-(CH3O)2(2.8) > 2,5-(CH3O)2(2.5) > 2,3-(CH3O)2 (2.1) > 3,5-(CH3O)2 (1.8) > 3,4-(CH3O)2 (0.9) > 2,4-(CH3O)2 (0.7). High Tg of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 250–400°C range with residue, which then decomposition in 400–800°C range.  相似文献   

6.
In aqueous H2SO4, Ce(IV) ion oxidizes rapidly Arnold's base((p-Me2NC6H4)2CH2, Ar2CH2) to the protonated species of Michler's hydrol((p-Me2NC6H4)2CHOH, Ar2CHOH) and Michler's hydrol blue((p-Me2NC6H4)2CH+, Ar2CH+). With Ar2CH2 in excess, the rate law of the Ce(IV)-Ar2CH2 reaction in 0.100 M H2SO4 is expressed -d[Ce(IV)]/dt = kapp[Ar2CH2]0[Ce(IV)] with kapp = 199 ± 8M?1s?1 at25°C. When the consumption of Ce(IV) ion is nearly complete, the characteristic blue color of Ar2CH+ ion starts to appear; later it fades relatively slowly. The electron transfer of this reaction takes place on the nitrogen atom rather than on the methylene carbon atom. The dissociation of the binuclear complex [Ce(III)ArCHAr-Ce(III)] is responsible for the appearance of the Ar2CH+ dye whereas the protonation reaction causes the dye to fade. In highly acidic solution, the rate law of the protonation reaction of Michler's hydrol blue is -d[Ar2CH+]/dt = kobs[Ar2CH+] where Kobs = ((ac + 1)[H*] + bc[H+]2)/(a + b[H+]) (in HClO4) and kobs= ((ac + 1 + e[HSO4?])[H+] + bc[H+]2 + d[HSO4?] + q[HSO4?]2/[H+])/(a + b[H+] + f[HSO4?] + g[HSO4?]/[H+]) (in H2SO4), and at 25°C and μ = 0.1 M, a = 0.0870 M s, b = 0.655 s, c = 0.202 M?1s?1, d = 0.110, e = 0.0070 M?1, f = 0.156 s, g = 0.156 s, and q = 0.124. In highly basic solution, the rate law of the hydroxylation reaction of Michler's hydrol blue is -d[Ar2CH+]/dt = kOH[OH?]0[Ar2CH+] with kOH = 174 ± 1 M?1s?1 at 25°C and μ = 0.1 M. The protonation reaction of Michler's hydrol blue takes place predominantly via hydrolysis whereas its hydroxylation occurs predominantly via the path of direct OH attack.  相似文献   

7.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H2CH=C(CN)2 (where R is 2,4-(CH3O)2-3-CH3, 2,3,4-(CH3O)3, 2,4,5-(CH3O)3, 2,4,6-(CH3O)3, 3,4,5-(CH3O)3, 6-Br-3,4-(CH3O)2), 2,3,5-Cl3, 2,3,6-Cl3 and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 3,4,5-(CH3O)3(10.6) > 2,4,6-(CH3O)3(9.3) > 2,4,5-(CH3O)3 (5.4) > 2,3,4-(CH3O)3 (4.4) > 6-Br-3,4-(CH3O)2 (3.2) > 2,3,5-Cl3 (1.5) > 2,3,6-Cl3 (1.0) > 2,4-(CH3O)2-3-CH3 (0.7). High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–400°C range with residue, which then decomposed in the 400–800°C range.  相似文献   

8.

Electrophilic trisubstituted ethylene monomers, alkyl and alkoxy ring‐disubstituted 2‐phenyl‐1,1‐dicyanoethylenes, RC6H3CH?C(CN)2 (where R is 2,4‐(CH3)2, 2,5‐(CH3)2, 2,3‐(CH3O)2, 2,4‐(CH3O)2, 2,5‐(CH3O)2, 3,4‐(CH3O)2, 3‐C2H5O‐4‐CH3O, 4‐CH3O‐3‐CH3), were synthesized by piperidine catalyzed Knoevenagel condensation of ring‐disubstituted benzaldehydes and malononitrile, and characterized by CHN elemental analysis, IR, 1H‐ and 13C‐NMR. Novel copolymers of the ethylenes and vinyl acetate were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C‐NMR, GPC, DSC, and TGA. High T g of the copolymers, in comparison with that of polyvinyl acetate, indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the copolymers decompose in the 190–700°C range.  相似文献   

9.
The polymerization of norbornene with bis(β‐ketonaphthylamino) palladium(II), Pd{CH3C(O)CHC[N(naphthyl)]CH3}2, in combination with tris(pentafluorophenyl)borane (B(C6F5)3), was investigated by varying the B:Pd(II) molar ratio, monomer concentration, reaction temperature, and time. The catalytic activity was found to reach 2.8 × 104 gPolymer/(molPd?h) and the obtained polynorbornene (PNBE) was confirmed to be vinyl addition polymer and showed good thermo‐stability (Tdec > 350°C), but exhibited poor solubility in organic solvents due to the relative higher stereo regularity. Pd{CH3C(O)CHC[N(naphthyl)]CH3}2/B(C6F5)3 system is also an active catalyst for copolymerization of norbornene and 5‐norbornene‐2‐yl acetate (NBE‐OCOCH3) in toluene with moderate yields (in 9.2–36.5% yields) and produces the addition‐type copolymer with relatively high molecular weights (0.96 × 104–2.13 × 104 g/mol). The incorporation of functional group in the copolymer can be controlled up to 0.9–23.5 mol% by varying the NBE‐OCOCH3 monomer feed ratios from 10 to 90%. The copolymers are proved to be noncrystalline and show good solubility in common organic solvents and excellent thermal stability up to 350°C. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

10.
The asymmetric unit of the title compound, dipotassium bis[hexaaquanickel(II)] tris(μ2‐methylenediphosphonato)tripalladium(II) hexahydrate, K2[Ni(H2O)6]2[Pd3{CH2(PO3)2}3]·6H2O, consists of half a {[Pd{CH2(PO3)2}]3}6− anion [one Pd atom (4e) and a methylene C atom (4e) occupy positions on a twofold axis] in a rare `handbell‐like' arrangement, with K+ and [Ni(H2O)6]2+ cations to form the neutral complex, completed by three solvent water molecules. The {[Pd{CH2(PO3)2}]3}6− units exhibit close Pd...Pd separations of 3.0469 (4) Å and are packed via intermolecular C—H...Pd hydrogen bonds. The [KO9] and [NiO6] units are assembled into sheets coplanar with (011) and stacked along the [100] direction. Within these sheets there are [K4Ni4O8] and [K2Ni2O4] loops. Successive alternation of the sheets and [Pd{CH2(PO3)2}]3 units parallel to [001] produces the three‐dimensional packing, which is also supported by a dense network of hydrogen bonds involving the solvent water molecules.  相似文献   

11.
The β-aminovinylketone ligands CH3C(NH2)CHC(O)CH3 (1) and CH3C(NHCH3)CHC(O)CH3 (2) were synthesized from 2,4-pentandione by amination with a water solution of the appropriate amine in toluene at room temperature. The reactions of 1 and 2 with the PdCl2 salt in amine medium gave the volatile chelate metal complexes Pd[CH3C(NH)CHC(O)CH3]2 (3) and Pd[CH3C(NCH3)CHC(O)CH3]2 (4). The obtained compounds were identified by elemental analysis, 1H and 13С NMR, IR-spectroscopy and were characterized by TGA and a single-crystal X-ray diffraction study. In compounds 3 and 4, the Pd atom has a square coordination environment Pd O2N2.  相似文献   

12.
The fungicidal activity of a series of aryltin compounds, (p-ZC6H4)3SnX (X=OAc, OH, or 1/2O), where Z=F, Cl, CH3, CH3O, C2H5 or (CH3)3C, and for which IR and NMR (119Sn) data are reported, has been assessed by radial growth assays on Aspergillus niger, Botrytis cinera, Mucor hiemalis, Fusarium solani and Penicillium chrysogenum, and the results compared with those for the Ph3SnOAc and Ph3SnOH archetypes. In most cases, para-substitution only slightly reduces biocidal activity, but with p-CH3O the aryltin is completely ineffective. This result correlates with the seemingly decreased ability of the ‘(p-CH3OC6H4)3Sn’ moiety to achieve a trigonal-bipyramidal five-coordinate geometry with oxygen atoms in the axial positions, all other Ar3SnOAc and Ar3SnOH having this geometry in the solid state. A model for fungicidal action is proposed based on the need for the organotin inhibitor to attain the above geometry in the active site that it occupies in the ATPase enzyme, being the required condition for its biological activity. © 1997 John Wiley & Sons, Ltd.  相似文献   

13.
A series of dicationic PdII-acetonitrile complexes containing bi- and tridentate nitrogen and bidentate phosphine ligands (some of which are chiral) has been prepared as their BF4 salts. The molecular structures for two of these, [Pd(CH3CN)2(bipy)] (BF4)2 ( 4 ) and [Pd(CH3CN)((pybox)(i-Pr))] (BF4)2((S,S)-pybox(i-Pr) = 2,6-bis[(S)-4′-isopropyloxazolin-2′-yl]pyridine, 5 ) have been determined by X-ray diffraction. All of these complexes are shown to be effective homogeneous catalysts for the aldol-type condensation of the isonitrile, methyl isocyanoacetate, with benzaldehyde. Two isonitrile complexes, [Pd(2,2′-bipyridyl)(CNCH2COOCH3)2] (BF4)2 and [Pd((S,S)-pybox(i-Pr))(CNCH2COOCH3)] (BF4)2, have also been prepared.  相似文献   

14.
A series of 2-aminobiphenyl palladacycles supported by dialkylterphenyl phosphines, PR2Ar′ (R=Me, Et, iPr, Cyp (cyclopentyl), Ar′=ArDipp2, ArXyl2f, Dipp (2,6-C6H3-(2,6-C6H3-(CHMe2)2)2), Xyl=xylyl) have been prepared and structurally characterized. Neutral palladacycles were obtained with less bulky terphenyl phosphines (i.e., Me and Et substituents) whereas the largest phosphines provided cationic palladacycles in which the phosphines adopted a bidentate hemilabile k1-P,η1-Carene coordination mode. The influence of the ligand structure on the catalytic performance of these Pd precatalysts was evaluated in aryl amination reactions. Cationic complexes bearing the phosphines PiPr2ArXyl2 and PCyp2ArXyl2 were the most active of the series. These precatalysts have demonstrated a high versatility and efficiency in the coupling of a variety of nitrogen nucleophiles, including secondary amines, alkyl amines, anilines, and indoles, with electronically deactivated and ortho-substituted aryl chlorides at low catalyst loadings (0.25–0.75 mol % Pd) and without excess ligand.  相似文献   

15.
15N-NMR. parameters for the complexes trans-[MCl2 (15NH2 (CH2)5CH3)L] are reported; M = Pt, Pd, L = PBu, PMePh2, P (p-CH3? C6H4)3, AsBun3, AsMePh2, As (p-CH3C6H4)3, NH2 (CH2)5CH3 and (for Pt) C2H4. For both metals, the NMR. parameters depend on the trans-influence of the ligand L. The values 1J (195Pt, 15N) vary from 138 to 336 Hz and can be shown to correlate with the values 1J (195Pt, 31P) in the complexes trans-[PtCl2 (PBu)L]. There is a linear relation between the 15N chemical shifts in the complexes of the two metals. The reactions of the complexes sym-trans-[M2Cl4L2], M = Pd, Pt, L = a tertiary phosphine or arsine, with neutral ligands are described. 195Pt-, 31P- and 13C-NMR. data are reported.  相似文献   

16.
5 -C5H4[CH(CH3)OC(O)CH = CH2])Mn(CO)3, {η5—C5[CH-(CH3)OC(O)C(CH3)=CH2]]Mn(CO)3, and {η5—C5H4[CH(CH3)-OC(O)CH=C(CH3)2])Mn(CO)3 were synthesized (63, 57, and 51%, respectively) from {η5—C5H4[CH(CH3)OH])Mn(CO)3, toluene-sulfonic acid, and the acrylic, methacrylic, and dimethylacrylic acids, and from (η5-C5H4[CH(CH3)OH]}Mn(CO)3, pyridine, and the acrylic, methacrylic, and dimethylacrylic acyl chlorides [26, 48, and 25% (impure), respectively]. No product was obtained when NaH was used as the base in the latter method. The acrylate and methacrylate monomers were bulk homopolymerized at 65°C with AIBN (75% yield, Mn = 88,550 g/mol; 78% yield, Mn = 349,350 g/mol, respectively). The dimethylacrylate did not polymerize under these conditions. The polymers lost vinylcymantrene upon heating to 257 and 279°C, respectively. The polymers did not exhibit a clear Tg but were observed to soften at 85 and 160°C, respectively, and they could be pulled into fibers.  相似文献   

17.
The complexes [IrH(CO)(PPh3)3], trans-[IrCI(CO)- (PPh3)2], [RhH(PPh3)4], [Pd(PPh3)4], [Pt(trans-stilbene)(PPh3)2] and [Pt(η3-CH2-COCH2)-(PPh3)2] catalyse the rearrangement of Me3SiCH2C(O)CH2Cl to CH2?C(OSiMe3)-CH2Cl.  相似文献   

18.
The mass spectra of some (Z)α-(4-R′-phenyl)-β-(2-thienyl-5-R)acrylonitriles (R = H, CH3, Br; R′ = H, CH3O, CH3, Cl, NO2) at 70 eV are reported. Mass spectra exhibit pronounced molecular ions. The compound's where R = H, and CH3 are characterized by the occurrence of a strong [M - H]+ peak. Moreover, in all the compounds a m/z 177 peak occurs. In the compounds where R = H, [M - HS]* and [M - CHS]* ions are present except the nitroderivatives. Where R = CH3, [M - HS]+ ion occurs.  相似文献   

19.
Diacetylplatinum(II) complexes [Pt(COMe)2(N^N)] (N^N = bpy, 3a; 4,4′-t-Bu2-bpy, 3b) were found to undergo oxidative addition reactions with organyl halides. The reaction of 3a with methyl iodide and propargyl bromide led to the formation of the cis addition products (OC-6-34)-[Pt(COMe)2(R)X(bpy)] (R = Me, X = I, 4a; CH2C≡CH, X = Br, 4k). Analogous reactions of 3a with ethyl iodide, benzyl bromide, and substituted benzyl bromides, 3-(bromomethyl)pyridine, 2-(bromomethyl)thiophene, allyl bromide, and cyclohex-2-enyl bromide led to exclusive formation of the trans addition products (OC-6-43)-[Pt(COMe)2(R)X(bpy)] (X = I, R = Et, 4b; X = Br, R = CH2C6H5, 4c; CH2C6H4(o-Br), 4d; CH2C6H4(p-COOH), 4e; CH2-3-py (3-pyridylmethyl), 4f; CH2-2-tp (2-thiophenylmethyl), 4g; CH2CH=CH2, 4h; c-hex-2-enyl (cyclohex-2-enyl), 4i). All complexes 4 were characterized by microanalysis, 1H and 13C NMR and IR spectroscopy. Additionally, complexes 4a, 4f, and 4g were characterized by single-crystal X-ray diffraction analyses. Reactions of 3a and 3b with o-, m- and p-bis(bromomethyl)benzene, respectively, led to the formation of dinuclear platinum(IV) complexes [{Pt(COMe)2Br(N^N)}2-{μ-(CH2)2C6H4}] (5). These complexes were characterized by microanalysis, IR spectroscopy, and depending on their solubility by 1H and 13C NMR spectroscopy, too. A single-crystal X-ray diffraction analysis of complex [{Pt(COMe)2Br(bpy)}2{μ-m-(CH2)2C6H4}] (5b) confirmed its dinuclear composition. The solid-state structures of 4a, 4f, 4g, and 5b are discussed in terms of C–H···O and O–H···O hydrogen bonds as well as π–π stacking between aromatic rings.  相似文献   

20.
Novel electrophilic trisubstituted ethylene monomers, oxy ring-disubstituted 2-cyano-3-phenyl-2-propenamides, RC6H3CH? C(CN)CONH2 (where R is 2,3-(CH3O)2, 2,4-(CH3O)2, 2,5-(CH3O)2, 2,6-(CH3O)2, 3,4-(CH3O)2, 3,5-(CH3O)2, 3-CH3?4-CH3O, 3-C2H5O-4-CH3O, 3,4-(C6H5CH2O)2, 2-C6H5CH2O-3-CH3O, 3-C6H5CH2O-4-CH3O, 4-C6H5CH2O-3-CH3O) were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and cyanoacetamide, and characterized by CHN analysis, IR, 1H- and 13C-NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, AIBN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H- and 13C-NMR. High Tg of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 300–500°C range with residue (2–9% wt), which then decomposed in the 500–800°C range.  相似文献   

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