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1.
Palladium(II)‐Catalyzed Synthesis of Sulfinates from Boronic Acids and DABSO: A Redox‐Neutral,Phosphine‐Free Transformation 下载免费PDF全文
Alex S. Deeming Dr. Claire J. Russell Prof. Michael C. Willis 《Angewandte Chemie (International ed. in English)》2016,55(2):747-750
A redox‐neutral palladium(II)‐catalyzed conversion of aryl, heteroaryl, and alkenyl boronic acids into sulfinate intermediates, and onwards to sulfones and sulfonamides, has been realized. A simple Pd(OAc)2 catalyst, in combination with the sulfur dioxide surrogate 1,4‐diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO), is sufficient to achieve rapid and high‐yielding conversion of the boronic acids into the corresponding sulfinates. Addition of C‐ or N‐based electrophiles then allows conversion into sulfones and sulfonamides, respectively, in a one‐pot, two‐step process. 相似文献
2.
Sulfonylation of alkenes through photoredox‐catalyzed functionalization of alkenes with thiourea dioxide under visible‐light irradiation is achieved. The reaction of alkenes, thiourea dioxide and electrophiles provides a green and efficient access to alkyl sulfones and sulfonamides. A broad reaction scope is presented with good functional group compatibility and excellent regioselectivity. A plausible mechanism involving a radical addition process with sulfur dioxide radical anion (SO2‐) derived from the oxidation of sulfur dioxide anion (SO22–) is proposed, which is supported by fluorescence quenching experiments. 相似文献
3.
Palladium‐Catalyzed Synthesis of Ammonium Sulfinates from Aryl Halides and a Sulfur Dioxide Surrogate: A Gas‐ and Reductant‐Free Process 下载免费PDF全文
Edward J. Emmett Dr. Barry R. Hayter Prof. Michael C. Willis 《Angewandte Chemie (International ed. in English)》2014,53(38):10204-10208
Sulfonyl‐derived functional groups populate a broad range of useful molecules and materials, and despite a variety of preparative methods being available, processes which introduce the most basic sulfonyl building block, sulfur dioxide, using catalytic methods, are rare. Described herein is a simple reaction system consisting of the sulfur dioxide surrogate DABSO, triethylamine, and a palladium(0) catalyst for effective convertion of a broad range of aryl and heteroaryl halides into the corresponding ammonium sulfinates. Key features of this gas‐ and reductant‐free reaction include the low loadings of palladium (1 mol %) and ligand (1.5 mol %) which can be employed, and the use of isopropyl alcohol as both a solvent and formal reductant. The ammonium sulfinate products are converted in situ into a variety of sulfonyl‐containing functional groups, including sulfones, sulfonyl chlorides, and sulfonamides. 相似文献
4.
Application of Fundamental Organometallic Chemistry to the Development of a Gold‐Catalyzed Synthesis of Sulfinate Derivatives 下载免费PDF全文
Miles W. Johnson Scott W. Bagley Prof. Neal P. Mankad Prof. Robert G. Bergman Dr. Vincent Mascitti Prof. F. Dean Toste 《Angewandte Chemie (International ed. in English)》2014,53(17):4404-4407
The development of a gold(I)‐catalyzed sulfination of aryl boronic acids is described. This transformation proceeds through an unprecedented mechanism which exploits the reactivity of gold(I)–heteroatom bonds to form sulfinate anions. Further in situ elaboration of the sulfinate intermediates leads to the corresponding sulfones and sulfonamides, two pharmacophores routinely encountered in drug discovery. 相似文献
5.
Dean Marković Dr. Chandra M. R. Volla Dr. Pierre Vogel Prof. Dr. Adrián Varela‐Álvarez José A. Sordo Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(20):5969-5975
The first ene reactions of SO2 and unfunctionalized alkenes are reported. Calculations suggest that the endergonic ene reactions of SO2 with alkenes can be used to generate β,γ‐unsaturated sulfinyl and sulfonyl compounds. Indeed, in the presence of one equivalent of BCl3, the unstable sulfinic acid form stable sulfinic acid?BCl3 complexes that can be reacted in situ with NCS to generate corresponding sulfonyl chlorides, or with a base to generate corresponding sulfinates. The latter can be reacted with electrophiles to generate sulfones, or with silyl chloride to form β,γ‐unsaturated silyl sulfinates. The sulfinic acid?BCl3 complexes can be reacted with ethers that act as oxygen nucleophiles to produce corresponding sulfinic esters. Thus one‐pot, three‐component synthesis of β,γ‐unsaturated sulfonamides, sulfinyl esters and sulfones have been developed starting from alkenes and sulfur dioxide (reagent and solvent). 相似文献
6.
Yong Luo Hao Ding Jing-Song Zhen Xian Du Xiao-Hong Xu Han Yuan Yi-Hui Li Wan-Ying Qi Bing-Zhe Liu Shi-Man Lu Can Xue Qiuping Ding 《Chemical science》2021,12(27):9556
A novel arylation of sulfonamides with boronic acids to afford numerous diaryl sulfones via a visible light-mediated N–S bond cleavage other than the typical transition-metal-catalyzed C(O)–N bond activation is described. This methodology, which represents the first catalyst-free protocol for the sulfonylation of boronic acids, is characterized by its simple reaction conditions, good functional group tolerance and high efficiency. Several successful examples for the late-stage functionalization of diverse sulfonamides indicate the high potential utility of this method in pharmaceutical science and organic synthesis.The simple, catalyst-free sulfonylation of boronic acids with sulfonamides via a visible light-mediated N–S bond cleavage is described, affording diaryl sulfones with high efficiency. Late-stage functionalization of sulfonamide drugs was shown. 相似文献
7.
《化学:亚洲杂志》2017,12(4):465-469
A green approach for the generation of β‐keto sulfones through a reaction of aryldiazonium tetrafluoroborates and sulfur dioxide with silyl enol ether under catalyst‐ and additive‐free conditions has been realized. This reaction proceeds efficiently at room temperature and goes to completion in half an hour. During the reaction process, aryldiazonium tetrafluoroborate is treated with DABCO ⋅ (SO2)2 (DABCO=1,4‐diazabicyclo[2.2.2]octane) to provide a sulfonyl radical as the key intermediate, which then initiates the transformation. Oxidants or metal catalysts are avoided, and the presence of DABCO also plays an important role in the reaction. 相似文献
8.
Alejandro Gmez‐Palomino Josep Cornella 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(50):18403-18407
Reported here is a simple and practical functionalization of primary sulfonamides, by means of a pyrylium salt (Pyry‐BF4), with nucleophiles. This simple reagent activates the poorly nucleophilic NH2 group in a sulfonamide, enabling the formation of one of the best electrophiles in organic synthesis: a sulfonyl chloride. Because of the variety of primary sulfonamides in pharmaceutical contexts, special attention has been focused on the direct conversion of densely functionalized primary sulfonamides by a late‐stage formation of the corresponding sulfonyl chloride. A variety of nucleophiles could be engaged in this transformation, thus permitting the synthesis of complex sulfonamides, sulfonates, sulfides, sulfonyl fluorides, and sulfonic acids. The mild reaction conditions and the high selectivity of Pyry‐BF4 towards NH2 groups permit the formation of sulfonyl chlorides in a late‐stage fashion, tolerating a preponderance of sensitive functionalities. 相似文献
9.
Yaping Li Shihao Chen Ming Wang Xuefeng Jiang 《Angewandte Chemie (International ed. in English)》2020,59(23):8907-8911
A straightforward multicomponent decarboxylative cross coupling of redox‐active esters (N‐hydroxyphthalimide ester), sodium dithionite, and electrophiles was established to construct sterically bulky sulfones. The inorganic salt sodium dithionite not only served as the sulfur dioxide source, but also acted as an efficient radical initiator for the decarboxylation. Notably, diverse naturally abundant carboxylic acids and artificially prepared carboxyl‐containing drugs with multiple heteroatoms and sensitive functional groups successfully underwent this decarboxylative sulfonylation to provide sterically bulky tertiary sulfones. Mechanistic studies further demonstrated that decarboxylation was the rate‐determining step and occurred via a single‐electron transfer (SET) process with the assistance of sodium dithionite. 相似文献
10.
A Highly Efficient Catalyst for the Suzuki Cross‐coupling Reaction of 3‐Chloro‐5‐oxadiazol‐2‐yl Pyridine 下载免费PDF全文
A. M. Sajith K. K. Abdul Khader A. Muralidharan M. S. Ali Padusha H. P. Nagaswarupa 《Journal of heterocyclic chemistry》2015,52(6):1748-1757
A facile access to diversely substituted 3‐aryl/heteroaryl‐5‐oxadiazol‐2‐yl‐pyridines using PdCl2(dtbpf) as palladium precursor has been developed. The method is compatible with a wide range of aryl/heteroaryl boronic acids. 相似文献
11.
Lin Guo Adam Noble Varinder K. Aggarwal 《Angewandte Chemie (International ed. in English)》2021,60(1):212-216
The reaction of bicyclo[1.1.0]butyl pinacol boronic ester (BCB‐Bpin) with nucleophiles has been studied. Unlike BCBs bearing electron‐withdrawing groups, which react with nucleophiles at the β‐position, BCB‐Bpin reacts with a diverse set of heteroatom (O, S, N)‐centred nucleophiles exclusively at the α‐position. Aliphatic alcohols, phenols, carboxylic acids, thiols and sulfonamides were found to be competent nucleophiles, providing ready access to α‐heteroatom‐substituted cyclobutyl boronic esters. In contrast, sterically hindered bis‐sulfonamides and related nucleophiles reacted with BCB‐Bpin at the β′‐position leading to cyclopropanes with high trans‐selectivity. The origin of selectivity is discussed. 相似文献
12.
Dr. Jie Wang Dr. Tian Qin Dr. Tie‐Gen Chen Dr. Laurin Wimmer Jacob T. Edwards Dr. Josep Cornella Benjamin Vokits Dr. Scott A. Shaw Prof. Phil S. Baran 《Angewandte Chemie (International ed. in English)》2016,55(33):9676-9679
A transformation analogous in simplicity and functional group tolerance to the venerable Suzuki cross‐coupling between alkyl‐carboxylic acids and boronic acids is described. This Ni‐catalyzed reaction relies upon the activation of alkyl carboxylic acids as their redox‐active ester derivatives, specifically N‐hydroxy‐tetrachlorophthalimide (TCNHPI), and proceeds in a practical and scalable fashion. The inexpensive nature of the reaction components (NiCl2?6 H2O—$9.5 mol?1, Et3N) coupled to the virtually unlimited commercial catalog of available starting materials bodes well for its rapid adoption. 相似文献
13.
Hongyi Chen Liming Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(40):11941-11945
Donor‐substituted acyl gold carbenes are challenging to access selectively by gold‐promoted intermolecular oxidation of internal alkynes as the opposite regioisomers frequently predominate. By using alkynyl sulfones or sulfonates as substrates, the oxidative gold catalysis in the presence of substituted pyridine N‐oxides offers regiospecific access to acyl/aryl, acyl/alkenyl, and acyl/alkoxy gold carbenes by in situ expulsion of sulfur dioxide. The intermediacies of these reactive species are established by their reactivities, including undergoing further oxidation by the same oxidant, cyclopropanation of styrenes, engaging in a [3+2] cycloaddition with α‐methylstyrene, and conversion into dienones. 相似文献
14.
Roxan Joncour Dr. Nicolas Susperregui Noël Pinaud Dr. Karinne Miqueu Prof. Eric Fouquet Dr. Jean‐Marc Sotiropoulos Prof. François‐Xavier Felpin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(28):9291-9296
We describe the coupling of anilines with aryl boronic acids, under ligand‐, base‐, and salt‐free conditions at room temperature. This new reaction proceeds through the formation of an aryl palladium alkoxo complex, which allows the transmetalation step with aryl boronic acids without any external base. Importantly, this sustainable procedure generates only environmentally friendly byproducts such as tBuOH, H2O, N2, and B(OH)3. The reaction mechanism has been deeply investigated through experimental and theoretical studies. 相似文献
15.
A series of Pd(II)‐enaminone complexes, termed Pd(eao)2, have been synthesized and characterized. The investigation on the catalytic activities of these new Pd(II)‐reagents has proved that the Pd(eao)2‐ 1 possesses excellent catalytic activity for the Suzuki‐ Miyaura cross coupling reactions of aryl bromides/chlorides with aryl/vinyl boronic acids in the environmentally benign media of aqueous PEG400 at low loading (5 mol‰). The superiority of this Pd(II)‐reagent to those commercial Pd(II) and Pd(0) catalysts in catalyzing the reactions has been confirmed by parallel experiments. What's more, Pd(eao)2‐ 2 has been found as a practical catalyst for the homo‐coupling reactions of aryl boronic acids. 相似文献
16.
Achieving Simultaneous CO2 and H2S Conversion via a Coupled Solar‐Driven Electrochemical Approach on Non‐Precious‐Metal Catalysts 下载免费PDF全文
Dr. Weiguang Ma Hong Wang Dr. Wei Yu Xiaomei Wang Zhiqiang Xu Prof. Xu Zong Prof. Can Li 《Angewandte Chemie (International ed. in English)》2018,57(13):3473-3477
Carbon dioxide (CO2) and hydrogen sulfide (H2S) are generally concomitant with methane (CH4) in natural gas and traditionally deemed useless or even harmful. Developing strategies that can simultaneously convert both CO2 and H2S into value‐added products is attractive; however it has not received enough attention. A solar‐driven electrochemical process is demonstrated using graphene‐encapsulated zinc oxide catalyst for CO2 reduction and graphene catalyst for H2S oxidation mediated by EDTA‐Fe2+/EDTA‐Fe3+ redox couples. The as‐prepared solar‐driven electrochemical system can realize the simultaneous conversion of CO2 and H2S into carbon monoxide and elemental sulfur at near neutral conditions with high stability and selectivity. This conceptually provides an alternative avenue for the purification of natural gas with added economic and environmental benefits. 相似文献
17.
Shivanand Gajare Megha Jagadale Altafhusen Naikwade Prakash Bansode Gajanan Rashinkar 《应用有机金属化学》2019,33(6)
Ferrocene tethered N‐heterocyclic carbene‐copper complex anchored on graphene ([GrFemImi]NHC@Cu complex) has been synthesized by covalent grafting of ferrocenyl ionic liquid in the matrix of graphene followed by metallation with copper (I) iodide. The [GrFemImi]NHC@Cu complex has been characterized by fourier transform infrared (FT‐IR), fourier transform Raman (FT‐Raman), CP‐MAS 13C NMR spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), energy dispersive X‐ray (EDX) analysis, X‐ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) surface area analysis and X‐ray diffractometer (XRD) analysis. This novel complex served as a robust heterogeneous catalyst for the synthesis of bioactive N‐aryl sulfonamides from variety of aryl boronic acids and sulfonyl azides in ethanol by Chan‐Lam coupling. Recyclability experiments were executed successfully for six consecutive runs. 相似文献
18.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(39):12143-12147
A palladium‐catalyzed C(sp3)−C(sp2) Suzuki–Miyaura cross‐coupling of aryl boronic acids and α‐(trifluoromethyl)benzyl tosylates is reported. A readily available, air‐stable palladium catalyst was employed to access a wide range of functionalized 1,1‐diaryl‐2,2,2‐trifluoroethanes. Enantioenriched α‐(trifluoromethyl)benzyl tosylates were found to undergo cross‐coupling to give the corresponding enantioenriched cross‐coupled products with an overall inversion in configuration. The crucial role of the CF3 group in promoting this transformation is demonstrated by comparison with non‐fluorinated derivatives. 相似文献
19.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(1):57-60
Organic phosphonic acids and organic phosphonic acid esters have been of much interest due to their applications in the fields of medicine, agriculture and industrial chemistry. Boronic acids can act as synthetic intermediates and building blocks and are used in sensing, protein manipulation, therapeutics, biological labelling and separation. The additional introduction of an aminophosphonic acid group into a boronic acid may give new opportunities for application. To study the structure of such multifunctional compounds, we prepared two new derivatives which can be easily converted to the corresponding phosphonic acids. In the title compounds, {4‐[(butylamino)(diethoxyphosphoryl)methyl]phenyl}boronic acid monohydrate, C15H27BNO5P·H2O, (I), and {4‐[(diethoxyphosphoryl)(4‐nitroanilino)methyl]phenyl}boronic acid, C17H22BN2O7P, (II), three different substituents are attached to a central C—H group, namely 4‐boronophenyl, diethoxyphosphoryl and amine. Compound (I) crystallizes as a monohydrate and OB—H…N hydrogen bonds link neighbouring molecules into chains along the [001] direction. The solvent water molecule connects two such chains running in opposite directions. Compound (II) crystallizes as an ansolvate and classical hydrogen bonds result in a layer structure in the (001) plane. 相似文献
20.
Jana Sopkov‐de Oliveira Santos Jean‐Charles Lancelot Alexandre Bouillon Sylvain Rault 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o111-o113
The first comparative study between two new heterocyclic boron derivatives, viz. a (6‐bromopyridin‐3‐yl)boronic ester, C11H15BBrNO2, and (6‐bromopyridin‐3‐yl)boronic acid, C5H5BBrNO2, shows a small but not significant difference in their C—B bond lengths, which cannot explain the experimentally observed difference in their stabilities. The crystal packing of the boronic ester consists principally of van der Waals interactions, while the boronic acid molecules interact in their crystal through hydrogen bonds. 相似文献