41448-64-0Relevant articles and documents
Visible-Light-Mediated Z -Stereoselective Monoalkylation of β,β-Dichlorostyrenes by Photoredox/Nickel Dual Catalysis
Abdellaoui, Mehdi,Millanvois, Alexandre,Levernier, Etienne,Ollivier, Cyril,Fensterbank, Louis
supporting information, p. 1513 - 1518 (2021/02/26)
Metal-catalyzed alkylation of 1,1-dihalovinyl moiety commonly suffers from both a lack of stereoselectivity and the overreaction leading to the dialkylation product. The methodology described herein features a new pathway to alkylate stereoselectively β,β-dichlorostyryl substrates to provide the Z -trisubstituted olefin only with fair to good yields. This cross-coupling reaction bears on the smooth and photoinduced formation of a C-centered radical that engages in a nickel-catalyzed organometallic cycle to form the key C sp2-C sp3bond.
Efficient Multigram Approach to Acetylenes and CF3-ynones Starting from Dichloroalkenes Prepared by Catalytic Olefination Reaction (COR)
Muzalevskiy, Vasiliy M.,Sizova, Zoia A.,Diusenov, Arstan I.,Shastin, Alexey V.,Nenajdenko, Valentine G.
supporting information, p. 4161 - 4166 (2020/07/13)
A novel approach to terminal acetylenes based on catalytic olefination reaction COR of arylaldehydes to form dichloroalkenes followed by treatment with nBuLi was elaborated. This method is atom economical and displays high yields and effectivity. The corresponding alkynes can be prepared in up to 97 % yield. One pot procedure towards CF3-ynones was elaborated to provide these products in up to 87 % yield starting from dichloroalkenes.
Cross-coupling reactivity of 1,1-dichloroalkenes under palladium catalysis: Domino synthesis of diarylalkynes
Maddali, L. N. Rao,Meka, Suresh
supporting information, p. 4412 - 4418 (2018/03/21)
An efficient synthesis of diarylalkynes was achieved from the domino cross-coupling reaction of 1,1-dichloroalkenes with triarylbismuth reagents under palladium-catalyzed conditions. Under the established palladium protocol, 1,1-dichloroalkenes demonstrated hitherto unknown remarkable cross-coupling reactivity with organometallic triarylbismuth reagents to furnish functionalized diarylalkynes.
A Robust One-Step Approach to Ynamides
Tu, Yongliang,Zeng, Xianzhu,Wang, Hui,Zhao, Junfeng
supporting information, p. 280 - 283 (2018/01/17)
A robust one-step synthetic strategy for ynamide with cheap and easily available stock chemicals vinyl dichlorides and electron deficient amides as the starting material is described. In the absence of transition-metal catalyst, the reaction proceeds under mild reaction conditions in open air and thus rendering a convenient operation. This strategy is not only suitable for both terminal and internal ynamide synthesis but also amenable for large-scale preparation. Broad substrate scopes with respect to vinyl dichloride as well as electron-deficient amide were observed.
Ionic liquids as a reusable media for copper catalysis. Green access to alkenes using catalytic olefination reaction
Muzalevskiy, Vasily M.,Shastin, Aleksey V.,Shikhaliev, Namiq G.,Magerramov, Abel M.,Teymurova, Aytekin N.,Nenajdenko, Valentine G.
, p. 7159 - 7163 (2016/10/24)
It was demonstrated that ionic liquids are superb recyclable media for copper catalyzed reactions using catalytic olefination reaction as an example. As a result a novel green access to the halogenoalkenes was elaborated. Possibility to perform up to five reaction cycles without catalyst leaching and decreasing of the yield was demonstrated. A number of various ionic liquids was screened and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim] [BF4]) was found the solvent with highest efficiency. Mild conditions, high atom economy comparing to other known methods, low amounts of wastes and possibility to recover ionic liquid are the advantages of the proposed method.
Organic photoredox catalysis for the oxidation of silicates: Applications in radical synthesis and dual catalysis
Lévêque, Christophe,Chenneberg, Ludwig,Corcé, Vincent,Ollivier, Cyril,Fensterbank, Louis
supporting information, p. 9877 - 9880 (2016/08/11)
Metal free photooxidation of alkyl bis(catecholato)silicates with the organic dye 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN) allows the smooth formation of alkyl radicals. The latter can be efficiently engaged either with radical acceptors to provide homolytic addition products or in photoredox/nickel dual catalysis reactions to obtain cross-coupling products.
β-(Carbonatoxy)alkyl radicals: A new subset of β-(ester)alkyl radical fragmentation during copper(I)-mediated synthesis of 1,1-dichloro-1-alkenes
Ram, Ram N.,Tittal, Ram K.
, p. 4342 - 4345 (2014/07/22)
A new subset of β-(ester)alkyl radicals is presented. It is the first study on the chemistry of β-(alkoxycarbonyloxy)alkyl radicals that fill the gap in the spectrum of the migrating groups in β-(ester)alkyl radical reactions. The change from less nucleofugal (acetate) group to the more nucleofugal (carbonate) group in the spectrum of the migrating group changed the reaction path from rearrangement to fragmentation. This approach has been used for the synthesis of 1,1-dichloroalkenes in high yields. The formation of dichloroalkenes was accounted by the involvement of alkene radical cation and carbonate anion pair (a CIP) as a result of heterolysis of the CO bond of the carbonate at the β-position of the β-(alkoxycarbonyloxy)alkyl radical. The alkene radical cation was trapped by nucleophilic reaction with MeOH to form methyl ester.
The use of bromotrichloromethane in chlorination reactions
Newman, Stephen G.,Bryan, Christopher S.,Perez, Didier,Lautens, Mark
supporting information; experimental part, p. 342 - 346 (2011/03/18)
Carbon tetrachloride is no longer used as a common solvent due to its toxicity and harmful environmental impact. The synthesis of gem-dichloroalkenes from aldehydes by using triphenylphosphine typically requires carbon tetrachloride as a solvent. We report that stoichiometric bromotrichloromethane in acetonitrile can be used in place of solvent quantities of carbon tetrachloride in this transformation. Similarly, bromotrichloromethane in dichloromethane can be used for the room-temperature Appel reaction of benzyl alcohols to form benzyl chlorides, which is commonly carried out in refluxing carbon tetrachloride. Georg Thieme Verlag Stuttgart New York.
Suzuki-Miyaura cross-coupling of 1,1-dichloro-1-alkenes with 9-alkyl-9-BBN
Liron, Frederic,Fosse, Celine,Pernolet, Alban,Roulland, Emmanuel
, p. 2220 - 2223 (2007/10/03)
We addressed an unexplored application of the Suzuki-Miyaura protocol to the cross-coupling of 1,1-dichloro-1-alkenes with 9-alkyl-9-BBN. The use of bisphosphine ligands with a large P-Pd-P bite angle allowed us to synthesize Z-chlorinated internal alkenes in good yields resulting from a selective monocoupling process, a recurrent challenge with 1,1-dichloro-1-alkenes. Moreover, these monochlorinated olefins could be further transformed providing stereospecifically trisubstituted olefins.
Allylation and vinylation of aryl radicals generated from diazonium salts
Heinrich, Markus R.,Blank, Olga,Ullrich, Daniela,Kirschstein, Marcel
, p. 9609 - 9616 (2008/03/27)
(Chemical Equation Presented) Allylation and vinylation of aryl radicals generated from aryl diazonium salts provides rapid and efficient access to chlorinated and brominated derivatives of styrene and allylbenzene. Allyl chlorides were found to be better substrates than bromides due to decreased halogen transfer. Donor- and acceptor-substituted diazonium salts are well tolerated. The products represent important precursors for numerous further transformations.
