65674-14-8Relevant academic research and scientific papers
Merging shuttle reactions and paired electrolysis for reversible vicinal dihalogenations
Dong, Xichang,Roeckl, Johannes L.,Waldvogel, Siegfried R.,Morandi, Bill
, (2021/02/12)
Vicinal dibromides and dichlorides are important commodity chemicals and indispensable synthetic intermediates in modern chemistry that are traditionally synthesized using hazardous elemental chlorine and bromine. Meanwhile, the environmental persistence of halogenated pollutants necessitates improved approaches to accelerate their remediation. Here, we introduce an electrochemically assisted shuttle (e-shuttle) paradigm for the facile and scalable interconversion of alkenes and vicinal dihalides, a class of reactions that can be used both to synthesize useful dihalogenated molecules from simple alkenes and to recycle waste material through retro-dihalogenation. The reaction is demonstrated using 1,2-dibromoethane, as well as 1,1,1,2-tetrachloroethane or 1,2-dichloroethane, to dibrominate or dichlorinate, respectively, a wide range of alkenes in a simple setup with inexpensive graphite electrodes. Conversely, the hexachlorinated persistent pollutant lindane could be fully dechlorinated to benzene in soil samples using simple alkene acceptors.
Copper and Zinc Copromoted Bromo(chloro)trifluoromethylation of Alkenes and Alkynes with Trifluoromethanesulfonic Anhydride
Ouyang, Yao,Qing, Feng-Ling,Tong, Chao-Lai,Xu, Xiu-Hua
supporting information, p. 346 - 350 (2021/01/13)
The first copper and zinc copromoted trifluoromethylation using trifluoromethanesulfonic anhydride (Tf2O) as a trifluoromethylating reagent has been developed. The reaction of alkenes or alkynes with Tf2O in the presence of CuX2 (X = Br, Cl), Zn powder, and 2,2′-bipyridine affords bromo(chloro)trifluoromethylated products in good yields. CuX2 plays a dual role as the catalyst and halide source, whereas 2,2′-bipyridine acts as both the activation reagent and ligand.
One-Pot Strategy for Thiazoline Synthesis from Alkenes and Thioamides
Alom, Nur-E,Wu, Fan,Li, Wei
supporting information, p. 930 - 933 (2017/02/26)
A convenient synthesis of a privileged pharmaceutical motif, thiazoline is accomplished. This reaction utilizes simple and readily available alkene and thioamide substrates in an intermolecular fashion via a simple one-pot procedure. A wide range of functional groups is tolerated, and the thiazoline product has been further utilized for the synthesis of the corresponding β-aminothiol and thiazole from routine hydrolysis and oxidation protocols.
Asymmetric Synthesis of Functionalized trans-Cyclopropoxy Building Block for Grazoprevir
Xu, Feng,Zhong, Yong-Li,Li, Hongming,Qi, Ji,Desmond, Richard,Song, Zhiguo J.,Park, Jeonghan,Wang, Tao,Truppo, Matthew,Humphrey, Guy R.,Ruck, Rebecca T.
supporting information, p. 5880 - 5883 (2017/11/10)
A practical and asymmetric synthesis of a functionalized trans-cyclopropoxy building block for the preparation of the HCV NS3/4a protease inhibitor grazoprevir is reported. Intramolecular SN2 displacement-ring closure, followed by a Baeyer-Villiger oxidation, yields the desired trans-cyclopropanol with full control of diastereoselectivity. A terminal alkyne is then effectively installed using LiNH(CH2)2NEt2. Starting from (S)-epichlorohydrin, the cyclopropoxy building block is prepared in 51% overall yield with >99.8% optical purity without isolation of any intermediates.
Efficient bromination of olefins, alkynes, and ketones with dimethyl sulfoxide and hydrobromic acid
Song, Song,Li, Xinwei,Sun, Xiang,Yuan, Yizhi,Jiao, Ning
supporting information, p. 3285 - 3289 (2015/06/25)
The oxidative bromination of olefins, alkynes, and ketones has been developed with HBr as the brominating reagent and DMSO as the mild oxidant. The simple conditions, high bromide-atom-economy, as well as easy accessibility and low cost of DMSO and HBr make the present strategy prospective for the synthesis of dibrominated alkanes, dibrominated alkenes and α-bromoketones.
Rasta resin-triphenylphosphine oxides and their use as recyclable heterogeneous reagent precursors in halogenation reactions
Xia, Xuanshu,Toy, Patrick H.
, p. 1397 - 1405 (2014/07/22)
Heterogeneous polymer-supported triphenylphosphine oxides based on the rasta resin architecture have been synthesized, and applied as reagent precursors in a wide range of halogenation reactions. The rasta resin-triphenylphosphine oxides were reacted with either oxalyl chloride or oxalyl bromide to form the corresponding halophosphonium salts, and these in turn were reacted with alcohols, aldehydes, aziridines and epoxides to form halogenated products in high yields after simple purification. The polymersupported triphenylphosphine oxides formed as a byproduct during these reactions could be recovered and reused numerous times with no appreciable decrease in reactivity.
Organocatalysis as a safe practical method for the stereospecific dibromination of unsaturated compounds
Hernandez-Torres, Gloria,Tan, Bin,Barbas, Carlos F.
supporting information; experimental part, p. 1858 - 1861 (2012/06/18)
Organocatalytic stereospecific dibromination of a wide variety of functionalized alkenes was achieved using a stable, inexpensive halogen source, 1,3-dibromo 5,5-dimethylhydantoin, and a simple thiourea catalyst at room temperature. The presence of a tertiary amine enhanced the rate of the dibromination reaction, and yields were good in various solvents, including aqueous solvents. The procedure was extended to alkynes and aromatic rings and to dichlorination reactions by using the 1,3-dichloro hydantoin derivative.
Peptide-Based Inhibitors of the Hepatitis C Virus NS3 Protease: Structure-Activity Relationship at the C-Terminal Position
Rancourt, Jean,Cameron, Dale R.,Gorys, Vida,Lamarre, Daniel,Poirier, Martin,Thibeault, Diane,Llinàs-Brunet, Montse
, p. 2511 - 2522 (2007/10/03)
The structure-activity relationship at the C-terminal position of peptide-based inhibitors of the hepatitis C virus NS3 protease is presented. The observation that the N-terminal cleavage product (DDIVPC-OH) of a substrate derived from the NS5A/5B cleavag
Liquid crystals
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, (2008/06/13)
Compounds of the formula STR1 wherein n stands for the number 0 or 1; the rings A1, A2 and A3 represent 1,4-phenylene, 2-fluoro-1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also represents a 2,5-disubstituted pyrimidine ring or a trans-2,5-disubstituted m-dioxane ring; X1 represents a single covalent bond, --COO--, --OOC--, --CH2 CH2 --, p--C6 H4 --, --CH2 CH2 --p-- C6 H4 --, --CH2 CH2 --p--C6 H4 --CH2 CH2 -- or, insofar as the rings A1 and A2 represent 1,4-phenylene, also --NON--; R2 represents 1E-alkenyl, 2Z-alkenyl, 3E-alkenyl, 4-alkenyl or alkenyloxy, with the proviso that the oxygen atom in alkenyloxy is linked with a saturated carbon atom; and R1 signifies 1E-alkenyl, 2Z-alkenyl, 3E-alkenyl, 4-alkenyl or, insofar as R2 represents alkenyloxy, also alkyl, their manufacture, as well as liquid crystalline mixtures and the use for electro-optical purposes.
