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1.
The reaction of the ortho-alkynylarylimines 1 with allyltributylstannane and allyl chloride in the presence of allylpalladium chloride dimer (5 mol %) and Cu(OAc)2 (20 mol %) in CH3CN at 50 °C gave the 1,4-diallyl-1,2-dihydroisoquinolines 2 in good yields. Most probably, the reaction proceeds through tandem bis-allylation of the imine-alkyne functional groups with bis-π-allylpalladium.  相似文献   

2.
Gold-catalyzed isomerization of 2-alkynyl-1-tetralones afforded the corresponding 2-naphthylmethyl ketones in good to high yields. For example, the reaction of 2-{4-(methoxyphenyl)methyl}-2-(phenylethynyl)-3,4-dihydronaphthalen-1(2H)-one and 2-benzyl-2-(phenylethynyl)-3,4-dihydronaphthalen-1(2H)-one in the presence of 5 mol % of (Ph3P)AuCl and 5 mol % of AgOTf in THF at 50 °C gave 2-{1-(4-methoxyphenylmethyl)naphthalen-2-yl}-1-(4-methoxyphenyl)ethanone and 2-(1-benzylnaphthalen-2-yl)-1-phenylethanone in 85% and 96% yields, respectively. The present reaction proceeds through [1,2] alkyl migration followed by oxygen transfer.  相似文献   

3.
Treatment of 3-en-1-ynyl imines with TpRuPPh3(CH3CN)2PF6 catalyst (1 mol %) in DCE (50 °C, 6 h) effected catalytic cyclization with suitable nucleophiles and gave functionalized pyrroles in good yields. The reaction mechanism is proposed to proceed via (2-pyrrolyl)carbenoid intermediates derived from 5-exo-dig cyclization. This catalytic reaction works well with various nucleophiles, including water, alcohols and anilines.  相似文献   

4.
The chemical kinetics, studied by UV/Vis, IR and NMR, of the oxidative addition of iodomethane to [Rh((C6H5)COCHCOR)(CO)(PPh3)], with R = (CH2)nCH3, n = 1-3, consists of three consecutive reaction steps that involves isomers of two distinctly different classes of RhIII-alkyl and two distinctly different classes of RhIII-acyl species. Kinetic studies on the first oxidative addition step of [Rh((C6H5)COCHCOR)(CO)(PPh3)] + CH3I to form [Rh((C6H5)COCHCOR)(CH3)(CO)(PPh3)(I)] revealed a second order oxidative addition rate constant approximately 500-600 times faster than that observed for the Monsanto catalyst [Rh(CO)2I2]. The reaction rate of the first oxidative addition step in chloroform was not influenced by the increasing alkyl chain length of the R group on the β-diketonato ligand: k1 = 0.0333 ([Rh((C6H5)COCHCO(CH2CH3))(CO)(PPh3)]), 0.0437 ([Rh((C6H5)COCHCO(CH2CH2CH3))(CO)(PPh3)]) and 0.0354 dmmol−1 s−1 ([Rh((C6H5)COCHCO(CH2CH2CH2CH3))(CO)(PPh3)]). The pKa and keto-enol equilibrium constant, Kc, of the β-diketones (C6H5)COCH2COR, along with apparent group electronegativities, χR of the R group of the β-diketones (C6H5)COCH2COR, give a measurement of the electron donating character of the coordinating β-diketonato ligand: (R, pKa, Kc, χR) = (CH3, 8.70, 12.1, 2.34), (CH2CH3, 9.33, 8.2, 2.31), (CH2CH2CH3, 9.23, 11.5, 2.41) and (CH2CH2CH2CH3, 9.33, 11.6, 2.22).  相似文献   

5.
We have found that the use of [Rh(cod)OH]2 associated with the water-soluble ligand m-TPPTC was highly efficient for the Rh-catalyzed arylation of alkynes. Aryl and alkyl alkynes were transformed to alkenes using 3 mol % rhodium catalyst and 2.5 equiv of boronic acid at 100 °C in a biphasic water/toluene system in 80-99% yield. The reaction was found to be totally regioselective for alkyl arylalkynes and alkyl silylated alkynes. The Rh/m-TPPTC system was for the first time recycled with no loss of the activity and with excellent purity of the desired alkene.  相似文献   

6.
Aryl amines undergo smooth annulation with O-phenylpropynyl sugar aldehyde in the presence of the Ph3PAuCl (10 mol %)/AgSbF6 (10 mol %) catalytic system to afford the corresponding tetrahydro-3aH-spiro[[1,3]dioxolo[4″,5″:4′,5′]furo[3′,2′:5,6]pyrano[4,3-b]quinoline-2,1′-cyclohexane] derivatives in good yields and selectivity.  相似文献   

7.
Poly(allyl iminoalane-co-ethyl iminoalane)s {[HAlN(allyl)]m[HAlNEt]n; Allyl/Et-alanes}, have been prepared by reactions of lithium hydridoaluminate (LiAlH4) with a mixture of allylamine hydrochloride (CH2CHCH2NH2 · HCl; allylNH2 · HCl) and ethylamine hydrochloride (CH3CH2NH2 · HCl; EtNH2 · HCl) with various allyl/Et ratios. Spectroscopic analyses indicate that Allyl/Et-alane(1/3) (allyl/Et = 1/3) contains octamers possessing Al-H and C-H groups as well as CC, Al-N, and C-N bonds. The loss of aluminum during pyrolysis of Allyl/Et-alane(1/3) at 1600 °C under an Ar atmosphere is 15%, which is less than the value reported for the pyrolysis of poly(ethyliminoalane) (36%). The suppression can be ascribed to cross-linking reactions involving allyl groups (hydroalumination and polymerization of the allyl groups), judging from infrared (IR) and solid-state nuclear magnetic resonance (NMR) spectroscopy.  相似文献   

8.
A novel voltammetric sensor for O,O-dimethyl-(2,4-dichlorophenoxyacetoxyl)(3′-nitrophenyl)methinephosphonate (Phi-NO2) based on molecularly imprinted polymer (MIP) film electrode is constructed by using sol-gel technology. The sensor responds linearly to Phi-NO2 over the concentration range of 2.0 × 10−5 to 1.0 × 10−8 mol L−1 and the detection limit is 1.0 × 10−9 mol L−1 (S/N = 3). This sensor provides an efficient way for eliminating interferences from coexisting substances in the solution. The high sensitivity, selectivity and stability of the sensor demonstrates its practical application for a simple and rapid determination of Phi-NO2 in cabbage samples.  相似文献   

9.
A new 1,6-hexyldiamine heptaborate, [H3N(CH2)6NH3][B7O10(OH)3] (1), has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis, and thermogravimetric analysis. Compound 1 crystallizes in monoclinic system, space group P21/n with a=8.042(2) Å, b=20.004(4) Å, c=10.103(2) Å, and β=90.42(3)°. The anionic [B7O10(OH)3]n2n layers are interlinked via hydrogen bonding to form a 3D supramolecular network containing large channels, in which the templated [H3N(CH2)6NH3]2+ cations are located.  相似文献   

10.
In this study the development, validation and application of a new chromatographic method for the determination of glutathione (GSH) in wine samples is presented. The separation of the GSH was carried out using a sulfobetaine-based hydrophilic interaction chromatography (HILIC) analytical column whereas its detection was carried out spectrofluorimetrically (λext/λem = 340/455 nm) after post-column derivatization with o-phthalaldehyde. GSH was separated efficiently from matrix endogenous compounds of wines by using a mobile phase of 15 mmol L−1 CH3COONH4 (pH = 2.5)/CH3CN, 35/65% (v/v). The parameters of the post-column reaction (pH, amount concentration of the reagent and buffer solution, flow rate, length of the reaction coil) were investigated. The linear determination range for GSH was 0.25–5.0 μmol L−1 and the LOD was 19 nmol L−1. No matrix effect was observed, while the accuracy was evaluated with recovery experiments and was ranged between 89% and 108%.  相似文献   

11.
Treatment of bis(fluoroalkyl) phosphites (RFCH2O)2P(O)H, where RF was CF3 or C2F5 with sulfur in pyridine at 80 °C gave salts of structure [(RFCH2O)2P(O)SH]NC5H5 in 90 and 88% yield, respectively. The salts reacted with alkyl iodides in acetonitrile at 50 °C to furnish bis(fluoroalkyl) S-alkyl phosphorothiolates (RFCH2O)2P(O)SR, where R was Me, Et, n- and i-Pr (when RF = CF3) and Me (when RF = C2F5). Yields ranged from 21 to 57%. Bis(trifluoroethyl) S-methyl phosphorothiolate (CF3CH2O)2P(O)SMe underwent fluorination by silver(I) fluoride in acetonitrile at room temperature to yield the phosphorofluoridate (CF3CH2O)2P(O)F in 75% yield. Tris(fluoroalkyl) phosphorothionates (RFCH2O)3P = S, where RF was CF3, C2F5 and C3F7, were prepared in 30-34% yield by heating the tris(fluoroalkyl) phosphites (RFCH2O)3P and sulfur to 200 °C in a sealed tube for 8 h.  相似文献   

12.
The coupling of aldehydes or ketones with (2-(4-methoxyphenyl)-4-methylenetetrahydrofuran-3-yl)methanol in the presence of nitriles under the influence of 5 mol % tris(pentaflourophenyl)borane at room temperature afforded a novel series of cis-fused hexahydro-1H-furo[3,4-c]pyran derivatives in good yields with high selectivity. This is the first report on the synthesis of hexahydro-1H-furo[3,4-c]pyranyl amide through a sequential Prins/Ritter reactions using B(C6F5)3 as a mild Lewis acid.  相似文献   

13.
Treatment of [Fc-1-R1-1′-R2] (R1 = H, R2 = CH(O); R1 = H, R2 = CMe(O); R1 = R2 = CMe(O)) with LiCCCH2OLi (prepared in situ from HCCCH2OH and n-BuLi) affords the ferrocenyl-substituted but-2-yne-1,4-diol compounds of general formula [Fc-1-R1-1′-{CR(OH)CCCH2OH}] (R1 = R = H (1a); R1 = H, R = Me (1b); R1 = CMe(O), R = Me (1c)) in low to high yields, respectively (where Fc = Fe(η5-C5H4)2). In the case of the reactions of [Fc-1-R1-1′-R2] (R1 = H, R2 = CH(O); R1 = R2 = CMe(O)), the by-products [Fc-1-R1-1′-{CR(OH)(CH2)3CH3}] (R1 = R = H (2a); R1 = CMe(O), R = Me (2c)) along with minor quantities of [Fc-1,1′-{CMe(OH)(CH2)3CH3}2] (3) are also isolated; a hydrazide derivative of dehydrated 2c, [1-(CMeCHCH2CH2CH3)-1′-(CMeNNH-2,4-(NO2)2C6H3)] (2c′), has been crystallographically characterised. Interaction of 1 with Co2(CO)8 smoothly generates the alkyne-bridged complexes [Fc-1-R1-1′-{Co2(CO)6-μ-η2-CR(OH)CCCH2OH}] (R1 = R = H (4a); R1 = H, R = Me(4b); R1 = CMe(O), R = Me (4c)) in good yield. Reaction of 4a with PhSH, in the presence of catalytic quantities of HBF4 · OEt2, gives the mono- [Fc-1-H-1′-{Co2(CO)6-μ-η2-CH(SPh)CCCH2OH}] (5) and bis-substituted [Fc-1-H-1′-{Co2(CO)6-μ-η2-CH(SPh)CCCH2SPh}] (6) straight chain species, while with HS(CH2)nSH (n = 2,3) the eight- and nine-membered dithiomacrocylic complexes [Fc-1-H-1′-{cyclo-Co2(CO)6-μ-η2-CH(S(CH2)n-)CCCH2S-}] [n = 2 (7a), n = 3 (7b)] are afforded. By contrast, during attempted macrocyclic formation using 4b and HSCH2CH2OCH2CH2SH dehydration occurs to give [Fc-1-H-1′-{Co2(CO)6-μ-η2-C(CH2)CCCH2OH}] (8). Single crystal X-ray diffraction studies have been reported on 2c′, 4b, 4c, 7b and 8.  相似文献   

14.
The salts, [Ph2B{OCH2CH2N(Me)(CH2)n}2][Ph4B3O3] (n = 4, 5), were prepared in moderate yields in MeOH solution from reaction of Ph2BOBPh2 with [N(CH2)n(Me)(CH2CH2OH)][OH] and PhB(OH)2 in a 1:2:4 ratio. The reactions also lead to Ph3B3O3. Both salts were characterized by NMR (1H, 13C, 11B) IR, and single-crystal XRD studies. The salts are comprised of cationic monoborates (zwitterionic, 2N+ and 1B) and tetraphenylboroxinate anions.  相似文献   

15.
The enthalpies of solution of NaRb[B4O5(OH)4]·4H2O in approximately 1 mol dm−3 aqueous hydrochloric acid and of RbCl in aqueous (hydrochloric acid + boric acid + sodium chloride) were determined. From these results and the enthalpy of solution of H3BO3 in approximately 1 mol dm−3 HCl(aq) and of sodium chloride in aqueous (hydrochloric acid + boric acid), the standard molar enthalpy of formation of −(5128.02 ± 1.94) kJ mol−1 for NaRb[B4O5(OH)4]·4H2O was obtained from the standard molar enthalpies of formation of NaCl(s), RbCl(s), H3BO3(s) and H2O(l). The standard molar entropy of formation of NaRb[B4O5(OH)4]·4H2O was calculated from the Gibbs free energy of formation of NaRb[B4O5(OH)4]·4H2O computed from a group contribution method.  相似文献   

16.
Nitration of p-tert-butylcalix[n]arene methyl ethers under a variety of reaction conditions has been examined. It has been determined that amongst different nitration procedures adopted (AlCl3/KNO3, HNO3/CH3COOH, HNO3/(CH3CO)2O, cerium(IV) ammonium nitrate/CH3COOH), ipso-nitration with CH3COOH/HNO3 gives best yields of p-nitrocalixarenes and work up conditions. ipso-Nitration of tetramethoxytetra-p-tert-butylcalix[4]arene gives tetramethoxytetra-p-nitrocalix[4]arene as triclinic crystals with space group with a=9.102(3) Å, b=11.623(3) Å, c=18.368(3) Å and α=77.99(2)°, β=81.10(2)°, γ=73.37(2)°. Its conformation is partial cone and it forms an exocylic 1:1 complex with DMF.  相似文献   

17.
The reaction of PhHgOAc with N-NHCO-2-C4H3S-Htpp (5) and N-p-HNSO2C6H4tBu-Htpp (4) gave a mercury (II) complex of (phenylato) (N-2-thiophenecarboxamido-meso-tetra phenylporphyrinato)mercury(II) 1.5 methylene chloride solvate [HgPh(N-NHCO-2-C4H3S-tpp) · CH2Cl2 · 0.5C6H14;  6 · CH2Cl2 · 0.5C6H14] and a bismercury complex of bisphenylmercury(II) complex of 21-(4-tert-butyl-benzenesulfonamido)-5,10,15,20-tetraphenylporphyrin, [(HgPh)2(N-p-NSO2C6H4tBu-tpp); 7], respectively. The crystal structures of 6 · CH2Cl2 · 0.5C6H14 and 7 were determined. The coordination sphere around Hg(1) in 6 · CH2Cl2 · 0.5C6H14 and Hg(2) in 7 is a sitting-atop derivative with a seesaw geometry, whereas for the Hg(1) in 7, it is a linear coordination geometry. Both Hg(1) in 6 · CH2Cl2 · 0.5C6H14 and Hg(2) in 7 acquire 4-coordination with four strong bonds [Hg(1)–N(1) = 2.586(3) Å, Hg(1)–N(2) = 2.118(3) Å, Hg(1)–N(3) = 2.625(3) Å, and Hg(1)–C(50) = 2.049(4) Å for 6 · CH2Cl2 · 0.5C6H14; Hg(2)–N(1) = 2.566(6) Å, Hg(2)–N(2) = 2.155(6) Å, Hg(2)–N() = 2.583(6) Å, and Hg(2)–C(61) = 2.064(7) Å for 7]. The plane of the three pyrrole nitrogen atoms [i.e., N(1)–N(3)] strongly bonded to Hg(1) in 6 · CH2Cl2 · 0.5C6H14 and to Hg(2) in 7 is adopted as a reference plane 3N. For the Hg2+ complex in 6 · CH2Cl2 · 0.5C6H14, the pyrrole nitrogen bonded to the 2-thiophenecarboxamido ligand lies in a plane with a dihedral angle of 33.4° with respect to the 3N plane, but for the bismercury(II) complex in 7, the corresponding dihedral angle for the pyrrole nitrogen bonded to the NSO2C6H4tBu group is found to be 42.9°. In the former complex, Hg(1)2+ and N(5) are located on different sides at 1.47 and −1.29 Å from its 3N plane, and in the latter one, Hg(2)2+ and N(5) are also located on different sides at −1.49 and 1.36 Å form its 3N plane. The Hg(1)?Hg(2) distance in 7 is 3.622(6) Å. Hence, no metallophilic Hg(II)?Hg(II) interaction may be anticipated. NOE difference spectroscopy, HMQC and HMBC were employed to unambiguous assignment for the 1H and 13C NMR resonances of 6 · CH2Cl2 ·  0.5C6H14 in CD2Cl2 and 7 in CDCl3 at 20 °C. The 199Hg chemical shift δ for a 0.05 M solution of 7 in CDCl3 solution is observed at −1074 ppm for Hg(2) nucleus with a coordination number of four and at −1191 ppm for Hg(1) nucleus with a coordination number of two. The former resonance is consistent with that chemical shift for a 0.01 M solution of 6 in CD2Cl2 having observed at −1108 ppm for Hg(1) nucleus with a coordination number of four.  相似文献   

18.
Herein we report the use of commercially available P(i-PrNCH2CH2)3N (1a) as an efficient catalyst for 2-trimethylsilyl-1,3-dithiane (TMS-dithiane) addition to aldehydes at room temperature. The catalyst loading required for these reactions (5 mol %) is the lowest recorded in the literature, and the majority of the reaction times for this transformation are the shortest thus far reported. A variety of functional groups are tolerated on the aryl aldehyde substrates.  相似文献   

19.
A hyphenated ion-pair (tetrabutylammonium chloride—TBACl) reversed phase (C18) HPLC-ICP-MS method (High Performance Liquid Chromatography Inductively Coupled Plasma Mass Spectroscopy) for anionic Rh(III) aqua chlorido-complexes present in an HCl matrix has been developed. Under optimum chromatographic conditions it was possible to separate and quantify cationic Rh(III) complexes (eluted as a single band), [RhCl3(H2O)3], cis-[RhCl4(H2O)2], trans-[RhCl4(H2O)2] and [RhCln(H2O)6−n]3−n (n = 5, 6) species. The [RhCln(H2O)6−n]3−n (n = 5, 6) complex anions eluted as a single band due to the relatively fast aquation of [RhCl6]3− in a 0.1 mol L−1 TBACl ionic strength mobile phase matrix. Moreover, the calculated t1/2 of 1.3 min for [RhCl6]3− aquation at 0.1 mol kg−1 HCl ionic strength is significantly lower than the reported t1/2 of 6.3 min at 4.0 mol kg−1 HClO4 ionic strength. Ionic strength or the activity of water in this context is a key parameter that determines whether [RhCln(H2O)6−n]3−n (n = 5, 6) species can be chromatographically separated. In addition, aquation/anation rate constants were determined for [RhCln(H2O)6−n]3−n (n = 3-6) complexes at low ionic strength (0.1 mol kg−1 HCl) by means of spectrophotometry and independently with the developed ion-pair HPLC-ICP-MS technique for species assignment validation. The Rh(III) samples that was equilibrated in differing HCl concentrations for 2.8 years at 298 K was analyzed with the ion-pair HPLC method. This analysis yielded a partial Rh(III) aqua chlorido-complex species distribution diagram as a function of HCl concentration. For the first time the distribution of the cis- and trans-[RhCl4(H2O)2] stereoisomers have been obtained. Furthermore, it was found that relatively large amounts of ‘highly’ aquated [RhCln(H2O)6−n]3−n (n = 0-4) species persist in up to 2.8 mol L−1 HCl and in 1.0 mol L−1 HCl the abundance of the [RhCl5(H2O)]2− species is only 8-10% of the total, far from the 70-80% as previously proposed. A 95% abundance of the [RhCl6]3− complex anion occurs only when the HCl concentration is above 6 mol L−1. The detection limit for a Rh(III) species eluted from the column is below 0.147 mg L−1.  相似文献   

20.
Selective one-pot functionalization of methyl n-alkyl ketones, CnH2n+1COMe (n = 6-8) involving C-sp3-H bond cleavage with CO and various nucleophilic substrates [iPrOH, BuCH(Et)CH2OH, CF3CH2OH, (CF3)(Me)CHOH, H(CF2)2CH2OH, HCCCH2OH, furan, thiophene, and anisole] in the presence of the superelectrophilic system CBr4·2AlBr3 has been performed for the first time.  相似文献   

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