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1.
Vanessa Cerezo 《Tetrahedron》2007,63(42):10445-10453
Microwave irradiation efficiently promoted the Suzuki-Miyaura reaction of a 5-bromohistidine with various arylboronic acids in the presence of a palladium catalyst. This methodology allowed the synthesis of histidines substituted at position 5 of the imidazole ring with a phenyl, a substituted phenyl, a pyridyl or a thienyl ring. The corresponding 5-arylhistidines were obtained in moderate to good yields.  相似文献   

2.
Microwave irradiation efficiently promoted the solid-phase Suzuki-Miyaura reaction of a 5-bromohistidine with various arylboronic acids in the presence of a palladium catalyst. This methodology allowed the synthesis of peptides bearing a histidine residue substituted at position 5 of the imidazole ring with a phenyl, a substituted phenyl, a pyridyl, or a thienyl ring, as well as with the benzene ring of a tyrosine residue.  相似文献   

3.
The catalytic intermolecular cyclotrimerization of alkynylboronates, propargyl alcohols, and terminal alkynes was accomplished by means of the ruthenium catalysis and the temporary tethering approach with the C-B-O linkage to give rise to highly substituted arylboronates with excellent selectivity. The resultant arylboronates were further converted to highly substituted biaryls via the Suzuki-Miyaura coupling with various aryl iodides using Pd2(dba)3/PCy3 as a catalyst precursor in aqueous toluene. As a consequence, the four-component coupling approach to highly substituted biaryls was successfully established by combining these two operations into a sequential one-pot process.  相似文献   

4.
An efficient synthesis of biaryl building blocks with multiple point diversities via a Suzuki cross-coupling reaction using a commercially available preformed Pd catalyst 1 was reported. Substituted biaryl anilines and phenols were obtained in one step from commercially available aryl halides.  相似文献   

5.
Bis-8-hydroxyquinolines represent an important yet underexplored class of potential ligands for the preparation of various coordination polymers, which can be used in a plethora of applications. In this work, the synthesis of two types of bis-8-hydroxyquinolines, prepared via either an imination or a Suzuki-Miyaura coupling approach, as well as their analysis is discussed. Imination was pursued through the condensation of quinolinecarbaldehydes with diamines or aminoquinolines with dialdehydes, and the Suzuki-Miyaura coupling reactions were evaluated using a bromoquinoline substrate and diboronic acids.  相似文献   

6.
Seiji Yoshikawa 《Tetrahedron》2004,60(10):2225-2234
Novel 1-aryl-substituted 8-methoxynaphthalenes were conveniently prepared by using Suzuki-Miyaura cross-coupling as a key reaction. Chemical transformations of the coupled products gave a variety of biaryls bearing various functional groups. The optical behavior of the separated enantiomers of these derivatives was also investigated by HPLC analysis. The optical resolution and determination of absolute configuration of novel binaphtyl derivative were also described. These new compounds may have some potential as mono- or bidentate ligands for metal-catalyzed chemical transformations including asymmetric induction.  相似文献   

7.
The chemical synthesis of graphislactones A-D was achieved through the Pd-mediated intramolecular biaryl coupling reaction of phenyl benzoate derivatives.  相似文献   

8.
The development of a novel Suzuki-Miyaura method has been achieved to allow the efficient arylation of bromophenols. A range of functionality is tolerated with regard to the boronic acid coupling partner and the reaction exhibits complete chemoselectivity for the Caryl-Br bond versus the Caryl-Cl bond in the aryl halide input. The experimental protocol features a short reaction time of 15 min, utilizes inexpensive Pd/C as a catalyst, and is conducted with water as the solvent.  相似文献   

9.
彭文杰  韩秀文  俞飚 《中国化学》2006,24(9):1154-1162
A variety of 4'- and 3-C-aryl-quercetin derivatives were conveniently synthesized via Suzuki-Miyaura coupling of the corresponding quercetin-O-triflates with aryl boronic acids or boronates.  相似文献   

10.
卟啉阵列是通过桥接单元或键组装而成的多卟啉体系,其电子性质取决于桥接单元以及卟啉连接的位置。由于电子相互作用的卟啉阵列在光电子器件、传感器、光伏电池、非线性光学材料以及光动力治疗的染料等方面的潜在应用价值,在过去的几十年中,科学家们对其进行了大量探索。卟啉阵列的构筑主要包括非共价组装与共价组装两种方式,前者相对容易但构筑的阵列稳定性较差,后者相对较难但构筑的阵列稳定性较好。铃木偶联是指用零价钯催化卤代烃与烃基硼酸或硼酸酯交叉偶联的反应,它是构筑结构多样、性质各异的卟啉阵列的有效手段。本文主要对其近年来在构筑多卟啉阵列方面的研究进展进行综述。最后,展望了铃木偶联构筑卟啉阵列的发展趋势。  相似文献   

11.
A simple and efficient total synthesis of ellipticine was developed via the Suzuki-Miyaura coupling of sterically sensitive 2-hydroxybenzeneboronic acid with a multifunctional aryl halide using Pd(OAc)2 as a catalyst and Cu(OAc)2·H2O as an additive in DMSO/H2O as a key step followed by double N-arylation and cyclization.  相似文献   

12.
Suzuki-Miyaura coupling reactions of 5-chloro-1-phenyl-tetrazole with various functionalized arylboronic acids were investigated. In the presence of catalytic amounts of SPhos/Pd(OAc)2 or RuPhos/Pd(OAc)2, the reaction proceeded smoothly to afford 1,5-diaryltetrazoles in good to excellent yields.  相似文献   

13.
A solid-phase strategy for the synthesis of biaryl cyclic peptides containing a side-chain to side-chain His-Tyr linkage was developed. The key step was the macrocyclization of a linear peptidyl resin incorporating a 5-bromohistidine and a 3-boronotyrosine via the formation of the biaryl bond by means of a microwave-assisted Suzuki-Miyaura reaction. This method allowed direct access to biaryl cyclic peptides containing a 3- or 5-amino acid ring and bearing the histidine residue at the N- or the C-terminus, being especially conducive for analogues in which this amino acid is located at the C-terminus. This study also served to establish a strategy for the synthesis of biaryl cyclic peptides derived from the two hemispheres of the natural biaryl bicyclic peptides aciculitins.  相似文献   

14.
The electron rich and sterically bulky title phosphane was prepared and efficiently applied in the palladium catalyzed Suzuki-Miyaura cross-coupling reaction. With electron rich aryl chlorides and bromides the yields and reaction times were significantly improved by microwave heating.  相似文献   

15.
The synthesis of a new charge-neutral, air- and moisture-stable fluorinated bis(phenoxyketimine) Pd(II) complex is presented. Its activity as a precatalyst in the Suzuki-Miyaura cross-coupling reaction of activated and unactivated bromides has been explored.  相似文献   

16.
A new approach to the total synthesis of anthracycline natural products, nogalamycin and menogaril, was explored. The goal was to enable late-stage introduction of the EF-ring segment. The new synthetic route has been developed through strategic application of a Suzuki-Miyaura reaction as the key step, which coupled the EF-ring segment with the D-ring to give a 1,1′-disubsitituted alkene in good yield under biphasic conditions. Further manipulation of the coupling product completed the construction of the DEF-ring system.  相似文献   

17.
Amberlite IRA 402(OH) effectively mediates biarylation via Suzuki-Miyaura cross-coupling reaction on complex systems such as dihalo quinolonoquinoxalino-oxazocines.  相似文献   

18.
Eight new biaryl colchicinoids containing 3,4-methylene or benzodioxy ether bridges were synthesized. The key synthetic step employed a ligandless, aqueous Suzuki cross-coupling reaction catalyzed by Pd(OAc)2 with tetrabutylammonium bromide (TBAB) and potassium carbonate (K2CO3). The biaryl Suzuki products were typically formed in 5-30 min and always in less than 1 h.  相似文献   

19.
发展高效的不对称Suzuki-Miyaura偶联反应及其合成应用   总被引:1,自引:0,他引:1  
徐广庆  赵庆  汤文军 《有机化学》2014,(10):1919-1940
为解决不对称Suzuki-Miyaura交叉偶联反应中活性和选择性问题,我们设计并发展了一系列结构刚性的手性联芳基单膦配体.在发展高活性的大位阻交叉偶联反应方面,成功地实现了邻位四取代芳基芳基之间的Suzuki-Miyaura交叉偶联,并发展了官能团化的大位阻交叉偶联,在邻位二取代芳基溴苯与二级烷基硼酸之间的大位阻芳基烷基交叉偶联中也取得进展.在发展高立体选择性的交叉偶联反应方面,我们采用手性大位阻单膦配体和底物间次级作用相结合的设计理念,利用苯并噁唑啉酮辅基和芳基间的π-π作用,成功地发展了高立体选择性的邻位酰基化芳基芳基间不对称Suzuki-Miyaura偶联;利用极性基团双(2-氧代-3-噁唑烷基)次磷酰基(BOP)辅基和芳基间的极性π作用,成功地实现了应用性强的邻位氧基取代芳基芳基间高效不对称Suzuki-Miyaura偶联.最后我们首次将高效的不对称SuzukiMiyaura偶联方法学应用于天然产物合成,完成了手性联芳基天然产物Korupensamine A和Korupensamine B的高效不对称合成,并完成天然产物Michellamine B的立体选择性全合成.  相似文献   

20.
Sugar-protected 6-halouridine derivatives underwent Suzuki-Miyaura cross-coupling reactions with arylboronic acids in the presence of palladium(II) acetate as a catalyst, triphenylphosphine as a ligand, and sodium carbonate as a base. This methodology is applicable to both the C5- and C6-position of uridine and provides a direct access for versatile uridine derivatives.  相似文献   

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