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1.
The scope and limitations of the Pd(OAc)2/DABCO (1,4-diaza-bicyclo[2.2.2]octane)-catalyzed Suzuki-Miyaura cross-coupling reactions have been demonstrated. The results showed that the effect of solvent had a fundamental influence on the reaction. In the presence of Pd(OAc)2 and DABCO, both aryl bromides and aryl chlorides all worked well with arylboronic acids to form biaryls, heteroaryl-aryls, and biheteroaryls in moderate to excellent yields using DMF as the solvent. Additionally, the reactions of aryl bromides were conducted under relatively mild conditions. 相似文献
2.
PEG-400 [poly(ethylene glycol-400)] was found to improve the Pd(OAc)2/DABCO-catalyzed aqueous Suzuki-Miyaura and Stille cross-coupling reactions. In the presence of Pd(OAc)2, DABCO, and PEG-400, a variety of aryl halides were coupled with arylboronic acids or organotin compounds efficiently to afford the corresponding cross-coupled products in moderate to excellent yields. The turnover numbers was up to 900,000 for the Suzuki-Miyaura reaction and up to 9800 for the Stille reaction. The catalyst system was also effective for Heck and Sonogashira cross-coupling reactions to some extent. 相似文献
3.
Cu(OAc)2 catalyzed Sonogashira cross-coupling reaction in amines 总被引:4,自引:0,他引:4
Sheng Mei Guo Chen Liang Deng Jin Heng Li 《中国化学快报》2007,18(1):13-16
A simple Cu(OAc)_2 catalyzed Sonogashira coupling protocol is presented.It was found that the couplings of a variety of aryl halides with terminal alkynes were conducted smoothly to afford the corresponding desired products in moderate to excellent yields,using Cu(OAc)_2 as the catalyst and Et3N as the solvent. 相似文献
4.
The kinetics of acetoxylation of cyclododecene and (E,E,E)-1,5,9-cyclododecatriene catalyzed by Pd(OAc)2 has been studied in glacial acetic acid solutions at 323–343 K and atmospheric pressure. The experimental data were described
by kinetic equations of the Michaelis-Menten type. 相似文献
5.
在离子液体BMImPF6中, 用不同的钯催化剂和Lewis酸三氟甲磺酸铜Cu(OTf)2共催化苯乙烯二聚反应, 发现用Pd(OAc)2/Cu(OTf)2作催化剂, Pd/Cu物质的量之比为1~4时, 可高产率高选择性地获得苯乙烯二聚产物1,3-二苯基-1-丁烯. BMImPF6对催化剂有较好的溶解性, 可固定催化剂体系, 使催化剂有效地与产品分离. 同时, α-甲基苯乙烯的二聚反应表明, 室温下不发生反应, 提高温度有利于反应进行. 相似文献
6.
DMAP was found to accelerate significantly the rate of Pd(OAc)2 catalyzed Barbier type allylation of carbonyl compounds by allylbromide using SnCl2·2H2O as reducing agent. Both aldehyde as well as ketones produced excellent yields within a short reaction time in the presence of 3 mol % of Pd(OAc)2 and 12 mol % of DMAP at room temperature. Aldehydes could be allylated within 5–10 min whereas, in case of ketones, the reaction completes in 45–120 min. 相似文献
7.
[reaction: see text] An efficient Pd(OAc)2/Dabco-catalyzed Stille cross-coupling reaction procedure has been developed. In the presence of Pd(OAc)2 and Dabco (triethylenediamine), various aryl halides including aryl iodides, aryl bromides, and activated aryl chlorides were coupled efficiently with organotin compounds to afford the corresponding biaryls, alkene, and alkynes in good to excellent yields. Furthermore, high TONs [turnover numbers, up to 980,000 TONs for the coupling reaction of 1-bromo-4-nitrobenzene and furan-2-yltributyltin] for the Stille cross-coupling reaction were observed. 相似文献
8.
Reductive carbonylation of aryl and heteroaryl iodides using Pd(acac)2/dppm as an efficient catalyst
Abhilash S. SinghBhalchandra M. Bhanage Jayashree M. Nagarkar 《Tetrahedron letters》2011,52(18):2383-2386
Palladium catalyzed simple and efficient protocol for reductive carbonylation of aryl and heteroaryl compounds has been developed. The formylation of aryl and heteroaryl iodides takes place in the presence of Pd(acac)2/dppm catalyst at 10 bar pressure of synthetic gas to give the desired aromatic and heteroaromatic aldehydes in good to excellent yields. Easy work-up, stability of the catalyst, low catalyst loading and less reaction time are the advantages of this method. 相似文献
9.
A systematic investigation has been carried out for the allylation of carbonyl compounds under SnCl2·2H2O-mediated Barbier-type conditions, using CuI and Pd(OAc)2 as catalysts. Ketones, which are not reactive under the influence of CuI, however, could be activated by using Pd(OAc)2 as a catalyst. 相似文献
10.
Sung Hwan Kim 《Tetrahedron letters》2008,49(41):5863-5866
Regioselective ortho-hydroxylation of aryl moiety of 2-arylpyridines was carried out under the influence of Pd(OAc)2/Oxone (potassium peroxymonosulfate) in PEG-3400/t-BuOH in moderate yields. 相似文献
11.
Chao Sui Guang Lu Xin-yong Li Zhen-ping Qu Xue-jun Zou Guo-hua Chen 《Reaction Kinetics and Catalysis Letters》2008,94(2):191-198
The selective oxidation of cyclopentene to cyclopentanone catalyzed by Pd(CH3COO)2-NPMoV was investigated under atmospheric oxygen in aqueous acetonitrile acidified by CH3SO3H. It was shown that the conversion of cyclopentene and the yield of cyclopentanone was nearly 100% and 94.6%, respectively,
under the optimized reaction condition. 相似文献
12.
Rajesh G. KalkhambkarKenneth K. Laali 《Tetrahedron letters》2011,52(42):5525-5529
Polyfluoroarenes can be cross-coupled with simple aromatics (benzene, toluene, and anisole), in good isolated yields, by using Pd(OAc)2 dissolved in imidazolium ILs [(bmim)PF6 and (bmim)BF4] as solvent, without the need for an oxidant and an additive. The reaction is catalyzed by HOAc and it is subject to a primary isotope effect (KH/KD = 4.87). Competitive cross-coupling reactions of 1,2,4,5-tetrafluorobenzene with benzene/toluene, benzene/anisole, and anisole/toluene gave KB/KT = 5.1, KB/KA = 5.7, and KA/KT = 5.0, respectively, indicative of a remote substituent effect on Pd insertion into the phenyl C-H bond. Mild reaction conditions, simple product isolation and recycling/reuse of the IL are additional advantages of this method. 相似文献
13.
Rajesh G. KalkhambkarKenneth K. Laali 《Tetrahedron letters》2012,53(32):4212-4215
A facile, high yielding, method for the synthesis of a library of 2-aryl- and 2-heteroaryl-benzoxazoles and benzothiazoles from readily available Schiff bases is reported employing catalytic amounts of Pd(OAc)2 in imidazolium ionic liquids (bmim)BF4 and (bmim)PF6 without ligands and/or additives. Simple product isolation and recycling/re-use of the IL are additional advantages of this method. 相似文献
14.
B.V. Subba Reddy Zubeda Begum Y. Jayasudhan Reddy J.S. Yadav 《Tetrahedron letters》2010,51(25):3334-451
Indoles undergo smooth cyanation with CuCN in the presence of 20 mol % Pd(OAc)2 and 40 mol % CuBr2 in DMF to produce a wide range of the corresponding 3-cyanoindoles in good yields with high regioselectivity. 相似文献
15.
Noor-ul H. Khan Santosh Agrawal Sayed H.R. Abdi Eringathodi Suresh 《Tetrahedron letters》2008,49(4):640-644
The synthesis of α-aminonitriles of ketones and aldehydes was performed in very short reaction times (20 min) with excellent yields in the presence of 5 mol % of Fe(Cp)2PF6 under solvent-free conditions. 相似文献
16.
The Stille cross-coupling reaction of [1-11C]acetyl chloride with tributylphenylstannane leading to [carbonyl-11C]acetophenone was studied with the goal of developing a new 11C-labeling method for positron emission tomography tracer synthesis. The coupled product [carbonyl-11C]acetophenone was synthesized using the Pd2(dba)3/P(MeNCH2CH2)3N·HCl system with a 60-61% radiochemical conversion from [1-11C]acetyl chloride (decay-corrected, n = 3). 相似文献
17.
Salvatore GenoveseFrancesco Epifano Maria Carla MarcotullioCaroline Pelucchini Massimo Curini 《Tetrahedron letters》2011,52(27):3474-3477
Quinolines have been synthesized in very good yields from 2-aminoarylketones and differently substituted carbonyl compounds in the presence of Yb(OTf)3 as the catalyst. The method is applicable to both cyclic and acyclic carbonyl compounds with only slight differences in the experimental procedure. 相似文献
18.
C.J. Antony M. Junaid Bushiri Hema Tresa Varghese C. Yohannan Panicker Michel Fleck 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,73(5):942-945
Raman and FTIR spectra of guanidinium zinc sulphate [C(NH2)3]2Zn(SO4)2 are recorded and the spectral bands assignment is carried out in terms of the fundamental modes of vibration of the guanidinium cations and sulphate anions. The analysis of the spectrum reveals distorted SO42− tetrahedra with distinct S–O bonds. The distortion of the sulphate tetrahedra is attributed to Zn–O–S–O–Zn bridging in the structure as well as hydrogen bonding. The CN3 group is planar which is expressed in the twofold symmetry along the C–N (1) vector. Spectral studies also reveal the presence of hydrogen bonds in the sample. The vibrational frequencies of [C(NH2)3]2 and HC(NH2)3 are computed using Gaussian 03 with HF/6-31G* as basis set. 相似文献
19.
Rukhsana I. Kureshy Santosh Agrawal Noor-ul H. Khan Sayed H.R. Abdi E. Suresh 《Tetrahedron letters》2010,51(3):489-1708
Fe(Cp)2PF6 (5 mol %) efficiently catalyzed Mannich reaction of aldehydes, anilines, and ketones under solvent-free condition to give β-amino-ketones in high yield (up to 94%) within 30 min with anti-isomer in excess. Simple experimental conditions and product isolation procedure makes this protocol potential for the development of clean and environment-friendly strategy for the synthesis of β-amino-ketones. 相似文献
20.
A new polystyrene-anchored Pd(II) phenyldithiocarbazate complex is synthesized and characterized. This Pd-complex behaves as an efficient heterogeneous catalyst in the Heck coupling and copper-free Sonogashira coupling reactions under aerobic conditions. Furthermore, the catalyst shows good thermal stability and recyclability. 相似文献