1258403-16-5Relevant academic research and scientific papers
AuI-Catalyzed Hydroalkynylation of Haloalkynes
Diéz, Elena,Fernández, Rosario,Gómez-Bengoa, Enrique,Garciá-Fernández, Pedro D.,Iglesias-Sigu?nza, Javier,Lassaletta, José M.,Rivero-Jerez, Paula S.
, p. 16082 - 16089 (2020)
The AuI-catalyzed reaction between terminal alkynes and aromatic haloalkynes proceeds through divergent pathways depending on the nature of the catalyst counteranion. Thus, cationic complexes containing strongly basic NHC ligands and noncoordinating anions such as BArF4 catalyze the cis haloalkynylation of the terminal alkyne, whereas introduction of a weakly basic triflate counteranion results in the stereoselective hydroalkynylation of the haloalkyne, yielding haloenyne products in good yields and complete trans selectivity. Experimental and computational studies suggest that the hydroalkynylation reaction takes place via nucleophilic attack of the terminal alkyne to the C2 carbon of the activated haloalkyne, assisted by a concerted proton abstraction by the triflate, and that the protodeauration is the turnover-limiting step, in agreement with an observed primary kinetic isotope effect.
Access to Substituted Thiophenes through Xanthate-Mediated Vinyl C(sp2)-Br Bond Cleavage and Heterocyclization of Bromoenynes
Huang, Guoling,Li, Jian,Li, Jianrong,Li, Jiaming,Sun, Minghua,Zhou, Peng,Chen, Lu,Huang, Yubing,Jiang, Shaohua,Li, Yibiao
, p. 13037 - 13049 (2020/11/26)
An environmentally sustainable strategy for the chemoselective heterocyclization of bromoenynes through a transition-metal-free sulfuration/cyclization process is reported. Using inexpensive and safe EtOCS2K as a thiol surrogate and tetrabutylphosphonium bromide and H2O as a mixed solvent, the reaction provided a range of substituted thiophenes in moderate to good yields. In addition, 2,3,4,5-tetrasubstituted thiophenes were able to be prepared under mild reaction conditions by electrophilic heterocyclization with NH4I and EtOCS2K in good yields.
Highly efficient two-step synthesis of (Z)-2-halo-1-iodoalkenes from terminal alkynes
Chen, Zhengwang,Jiang, Huanfeng,Li, Yibiao,Qi, Chaorong
supporting information; experimental part, p. 8049 - 8051 (2011/01/03)
The easily accessible haloalkynes can be converted to (Z)-2-halo-1- iodoalkenes in high yields with excellent regio- and stereoselectivity. The method shows good functional group compatibility. The resulting products could find broad applications.
