Enantioselective Synthesis of Atropisomers Featuring Pentatomic Heteroaromatics by Pd-Catalyzed C-H Alkynylation was written by Zhang, Shuo;Yao, Qi-Jun;Liao, Gang;Li, Xin;Li, Han;Chen, Hao-Ming;Hong, Xin;Shi, Bing-Feng. And the article was included in ACS Catalysis in 2019.Recommanded Product: 113893-08-6 This article mentions the following:
In the presence of Pd(OAc)2 and L-tert-leucine, biaryl aldehydes containing five-membered rings such as I underwent enantioselective alkynylation with bromoalkynes such as (triisopropylsilyl)bromoacetylene mediated by silver(I) trifluoroacetate in AcOH/toluene to give nonracemic atropisomeric biaryls such as II. A wide range of atropisomers in which either C-N or C-C bonds serve as the atropisomeric axis and containing one or two five-membered rings at each end of the axis were obtained; various five-membered heteroarenes, including pyrroles, thiophenes, benzothiophenes, and benzofurans were compatible with the method. A nonracemic 3,3′-bisbenzothiophene was prepared in 93% ee by this method. DFT calculations of the racemization barriers for various biaryls indicated that the shape of the rings on the biaryl axis is important in determining the racemization barriers. In the experiment, the researchers used many compounds, for example, Benzo[b]thiophen-3-ylboronic acid (cas: 113893-08-6Recommanded Product: 113893-08-6).
Benzo[b]thiophen-3-ylboronic acid (cas: 113893-08-6) belongs to benzothiophene derivatives. Benzothiophene is a fused ring compound of thiophene ring and benzene ring, which is an important class of heterocycles with advantageous structures. Due to its aromaticity, thiophenes do not exhibit the same properties as conventional thioethers.Recommanded Product: 113893-08-6
Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem