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1.
Han-Jun Ai Chuang-Xu Cai Xinxin Qi Jin-Bao Peng Feng Zheng Xiao-Feng Wu 《Tetrahedron letters》2017,58(40):3846-3850
A palladium-catalyzed Heck reaction of in-situ generated benzylic iodides and styrenes has been achieved. The reaction proceeds in a one-pot manner through 1) addition perfluoroalkyl iodides to styrenes to give benzylic iodides, 2) followed by a palladium-catalyzed Heck coupling of the resulting benzylic iodides with the same alkenes in high regio- and stereoselectivity. A variety of perfluoroalkylated alkenes were obtained in moderate to excellent yields. 相似文献
2.
Perfluoroalkyl iodides reacted with sodium dithionite by radical process to give sulfinatodeiodination products, so it seems possible to trap the intermediary perfluoroalkyl radical chemically. Alkenes were added as the radical trap and the radical addition products of perfluoroalkyl iodides with alkenes were obtained. The products were 1:1 adducts or oligomers, varying according to the nature of alkenes used. The formation and the orientation of the addition of these products showed that radicals did take part in the reaction. The relative reactivity of addition reaction and sulfinatodeiodination and the effect of inhibitor on the reaction was also discussed. 相似文献
3.
The addition of gem-difluorinated alkyl iodides to alkynes initiated by AIBN neatly gave the corresponding difluoromethylene vinyl iodides among which the stereoselectivity of aromatic acetylenes was high. The further coupling reaction of E-phenyl difluoromethylene vinyl iodides with terminal alkynes in the presence of catalytic palladium afforded the substituted difluorinated enynes. 相似文献
4.
Reaction of perfluoroalkyl iodides with a series of alkynes under sulfinatodehalogenation condition gave a mixture of E/Z adducts very readily in high yield, thus constituted a mild, convenient and effective new method for the addition of perfluoroalkyl iodides to alkynes. Under the same condition, in the presence of 1-hexyne perfluoroalkyl bromide and 1,1,1-trichlorotrifluoroethane reacted only to give sulfinates as the major products. A radical mechanism was proposed for the addition reaction. 相似文献
5.
[reaction: see text] The palladium-catalyzed reaction of aryl iodides with acetic anhydride provides a straightforward and experimentally simple carbon monoxide-free route to acetophenones. The reaction tolerates a wide range of functionalized aryl iodides. Acetophenones are isolated in excellent yield with a variety of neutral, slightly electron-rich, and slightly electron-poor aryl iodides, whereas moderate yields are obtained with aryl iodides containing strongly electron-withdrawing substituents. 相似文献
6.
The inhibition of positronium formation in neopentane caused by the addition of some organic iodides through the measurements of the energy spectra of Doppler-broadened annihilation radiation has been studied by using a deconvolution technique. The observed results could be interpreted by the reaction or the selective interaction of the positrons or the hot positronium atoms with the solute molecules. The observed change of the momentum distribution curve by the addition of the organic iodides can be explained consistently by these interpretations. 相似文献
7.
Amino acid promoted CuI-catalyzed C-N bond formation between aryl halides and amines or N-containing heterocycles 总被引:1,自引:0,他引:1
CuI-catalyzed coupling reaction of electron-deficient aryl iodides with aliphatic primary amines occurs at 40 degrees C under the promotion of N-methylglycine. Using l-proline as the promoter, coupling reaction of aryl iodides or aryl bromides with aliphatic primary amines, aliphatic cyclic secondary amines, or electron-rich primary arylamines proceeds at 60-90 degrees C; an intramolecular coupling reaction between aryl chloride and primary amine moieties gives indoline at 70 degrees C; coupling reaction of aryl iodides with indole, pyrrole, carbazole, imidazole, or pyrazole can be carried out at 75-90 degrees C; and coupling reaction of electron-deficient aryl bromides with imidazole or pyrazole occurs at 60-90 degrees C to provide the corresponding N-aryl products in good to excellent yields. In addition, N,N-dimethylglycine promotes the coupling reaction of electron-rich aryl bromides with imidazole or pyrazole to afford the corresponding N-aryl imidazoles or pyrazoles at 110 degrees C. The possible action of amino acids in these coupling reactions is discussed. 相似文献
8.
The radical addition of polyfluoroalkyl iodides to carbon-carbon multiple bonds is one of the most important and general methods for synthesis of a variety of fluorine-containing organic compounds.[1] Studies in our laboratory on stulfinatodehalogenation reaction showed that sodium dithionite was a excellent initiation reagent for the addition of polyfluoroalkyl iodides, bromides and halocarbons to alkenes, alkynes and conjugated dienes effectively under mild conditions.[2] 相似文献
9.
[reaction: see text] An efficient cobalt-catalyzed reductive coupling reaction of alkyl halides with electron-withdrawing alkenes (CH(2)=CR(1)EWG, EWG = electron-withdrawing group) in the presence of water and zinc powder in acetonitrile to give the corresponding Michael-type addition product (RCH(2)CR(1)EWG) was described. The methodology is versatile such that unactivated primary, secondary, and tertiary alkyl bromides and iodides and various conjugated alkenes including acrylates, acrylonitrile, methyl vinyl ketone, and vinyl sulfone all successfully participate in this coupling reaction. For the alkyl halides used in the reaction, the iodides generally gave better yields compared to those of the corresponding bromides. It is a unique method employing CoI(2)dppe, zinc, and alkyl halides, affording conjugate addition products in high yields. Mechanistically, the reaction appears to follow an oxidative addition driven route rather than the previously reported radical route. 相似文献
10.
Nishino T Okada M Kuroki T Watanabe T Nishiyama Y Sonoda N 《The Journal of organic chemistry》2002,67(24):8696-8698
A convenient synthetic method of unsymmetrical selenides has been developed. When diphenyl diselenide was allowed to react with two equimolar amounts of primary alkyl iodides and bromides in the presence of an equimolar amount of lanthanum metal, alkyl phenyl selenides were formed in moderate to good yields. For the reaction of primary alkyl chlorides and secondary alkyl iodides, the yields of the selenides were low; however, the yields were dramatically improved by the addition of TMEDA or HMPA. A reaction pathway involving the generation of a lanthanum phenylselenolate intermediate was suggested. 相似文献
11.
Yaoping ZhuXueyan Yang Xiang FangXianjin Yang LingLing YeWei Cai Yan ZhangFanhong Wu 《Tetrahedron》2011,67(6):1251-1257
Pent-4-en-1-amines are reactive to fluoroalkyl iodides with respect to sodium dithionite initiated free radical addition reactions. We report here the development of a novel and efficient synthesis of 2-fluoroalkyl pyrrolidine derivatives by sodium dithionite initiated one-pot reaction of pent-4-en-1-amines bearing various protecting groups with fluoroalkyl iodides. Among which, the N-benzyl-pent-4-en-1-amine exhibited the best tolerance toward the reaction condition in the present study, affording the desired adducts 3 in moderate to good yields of 65-85%. 相似文献
12.
《Tetrahedron letters》1988,29(40):5129-5130
Samarium diiodide was found to be an effective initiator in the addition reaction of fluoroalkyl iodides to olefins. 相似文献
13.
J.G. Duboudin B. Jousseaume A. Bonakdar A. Saux 《Journal of organometallic chemistry》1979,168(2):227-232
Iodination of γ-functionally substituted vinylic Grignard reagents, prepared by addition of organomagnesium compounds to α-aactylenic or α-allenic alcohols gives vinyl iodides stereospecifically. Treatment of these iodides with Grignard reagents in the presence of (PPh3)2NiCl2 gives allylic alcohols. This reaction proceeds with high stereoselectivity. 相似文献
14.
Suárez RM Pérez Sestelo J Sarandeses LA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(17):4179-4187
The stereoselectivity of the ultrasonically induced zinc--copper conjugate addition of iodides to chiral alpha,beta-unsaturated carbonyl systems under aqueous conditions was studied. Alkyl iodides add diastereoselectively to methylenedioxolanone 1 and methyleneoxazolidinone 2 to afford the 1,4-addition products in good yields (38-95 %) and with high diastereomeric excess (44-90 % de). The 1,4-addition to chiral gamma,delta-dioxolanyl-alpha,beta-unsaturated esters 3-5 also proceeds with good yields (51-99 %). The diastereoselectivity is dependent on the geometry of the olefin: the Z isomer 3 gives high diastereoselectivity, while the reactions with the E isomer 4 are nonstereoselective. The reaction proceeds with excellent chemoselectivity and allows the use of iodides bearing ester, hydroxy, and amino groups. Since the 1,4-addition products can be readily hydrolyzed, this methodology constitutes a novel entry for the enantioselective synthesis of alpha- and gamma-hydroxy acids and alpha-amino acids in aqueous media. The results obtained support the radical mechanism proposed by Luche, and represent one of the few examples of a radical stereoselective conjugate addition in aqueous medium. 相似文献
15.
Decarboxylative Conjunctive Cross-coupling of Vinyl Boronic Esters using Metallaphotoredox Catalysis
Riccardo S. Mega Vincent K. Duong Dr. Adam Noble Prof. Dr. Varinder K. Aggarwal 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4405-4409
The synthesis of complex alkyl boronic esters through conjunctive cross-coupling of vinyl boronic esters with carboxylic acids and aryl iodides is described. The reaction proceeds under mild metallaphotoredox conditions and involves an unprecedented decarboxylative radical addition/cross-coupling cascade of vinyl boronic esters. Excellent functional-group tolerance is displayed, and application of a range of carboxylic acids, including secondary α-amino acids, and aryl iodides provides efficient access to highly functionalized alkyl boronic esters. The decarboxylative conjunctive cross-coupling was also applied to the synthesis of sedum alkaloids. 相似文献
16.
An efficient ligand-free Stille coupling reaction catalyzed by palladium on charcoal was developed. Tetraphenyltin was reacted with a variety of aryl halides including aryl chlorides using LiCl as an additive. The reactions of tributyl organotin compounds with aryl iodides were effectively expedited by the addition of LiF. These reactions efficiently proceeded without a phosphine or arsenic ligand and no leached palladium was detected in the reaction mixture. 相似文献
17.
Xueyan Yang Dr. Xianjin Yang Shengjie Zhu Lingling Ye Yang Chen Guanlong Chen Prof. Dr. Fanhong Wu 《中国化学》2010,28(11):2269-2273
4‐Fluoroalkyl‐2‐acylamino‐4‐butyrolactones were afforded in moderate yields by the sodium dithionite initiated one‐pot addition‐lactonization reaction of polyfluoroalkyl iodides with 2‐acylamino‐4‐pentenoic acids. 相似文献
18.
19.
The reaction of iodides 1 with delta-chloropropylamines 5 in MeCN assisted with K2CO3 undergoes a sequential S(N)2/Michael addition/SN2/SN2 reaction process to give polysubstituted indolizidines and quinolizidines. Using this method, indolizidine 223A is synthesized from 2-ethyl-2-hexenoic acid in 12 linear steps and 14.5% overall yield. [Reaction: see text] 相似文献