108983-34-2Relevant academic research and scientific papers
Gold(I)-Catalyzed Synthesis of Highly Substituted 1,4-Dicarbonyl Derivatives via Sulfonium [3,3]-Sigmatropic Rearrangement
Zhou, Weiping,Voituriez, Arnaud
, p. 247 - 252 (2021)
An efficient and straightforward gold-catalyzed protocol for the synthesis of 2-substituted 4-oxo-4-arylbutanal derivatives from commercially available or easily accessible alkynes and vinylsulfoxide substrates has been developed. Extension of the methodology to the use of 1-cycloalkenyl sulfoxides allowed the facile synthesis of five-, six-, and seven-membered-ring cycloalkyl-1-one backbone. Subsequently, the tetrahydrocycloalkyl[b]pyrrole derivatives, which are found in many active pharmaceutical ingredients, were isolated in good yields. Mechanistic investigation highlighted a [3,3]-sigmatropic rearrangement of a sulfonium intermediate in this process.
Transition-Metal-Free Sulfuration/Annulation of Alkenes: Economical Access to Thiophenes Enabled by the Cleavage of Multiple C-H Bonds
Chen, Liang,Min, Hao,Zeng, Weilan,Zhu, Xiaoming,Liang, Yun,Deng, Guobo,Yang, Yuan
supporting information, p. 7392 - 7395 (2019/01/03)
A novel, atom economical, and transition-metal-free strategy for the synthesis of thiophenes from substituted buta-1-enes with potassium sulfide has been presented. The reaction achieves double C-S bond formations via cleavage of multiple C-H bonds and provides an efficient approach to access various functionalized thiophenes. Moreover, the strategy can also be used for the synthesis of thiophenes from 1,4-diaryl-1,3-dienes. Mechanistically, DMSO plays a role of oxidant and S3?- in situ generated from K2S is involved.
Kinetic Studies on the Palladium(II)-Catalyzed Oxidative Cross-Coupling of Thiophenes with Arylboron Compounds and Their Mechanistic Implications
Schnapperelle, Ingo,Breitenlechner, Stefan,Bach, Thorsten
supporting information, p. 18407 - 18416 (2015/12/24)
Reaction orders for the key components in the palladium(II)-catalyzed oxidative cross-coupling between phenylboronic acid and ethyl thiophen-3-yl acetate were obtained by the method of initial rates. It turned out that the reaction rate not only depended on the concentration of palladium trifluoroacetate (reaction order: 0.97) and phenylboronic acid (reaction order: 1.26), but also on the concentration of the thiophene (reaction order: 0.55) and silver oxide (reaction order: -1.27). NMR spectroscopy titration studies established the existence of 1:1 complexes between the silver salt and both phenylboronic acid and ethyl thiophen-3-yl acetate. A low inverse kinetic isotope effect (kH/kD=0.93) was determined upon employing the 4-deuterated isotopomer of ethyl thiophen-3-yl acetate and monitoring its reaction to the 4-phenyl-substituted product. A Hammett analysis performed with para-substituted 2-phenylthiophenes gave a negative ρ value for oxidative cross-coupling with phenylboronic acid. Based on the kinetic data and additional evidence, a mechanism is suggested that invokes transfer of the phenyl group from phenylboronic acid to a 1:1 complex of palladium trifluoroacetate and thiophene as the rate-determining step. Proposals for the structure of relevant intermediates are made and discussed.
Synthesis of unsymmetrical 2,3-diaryl- and 2,4-diarylthiophenes starting from 2,5-dichlorothiophene
Sone,Sato,Umetsu,Yoshino,Takahashi
, p. 2187 - 2194 (2007/10/02)
Unsymmetrically substituted 2,4-diaryl- and 2,3-diarylthiophenes were synthesized from 2,5-dichlorothiophene via 4-aryl-2-chlorothiophenes in two and four steps including Ni-mediated cross-coupling, respectively. Aluminum chloride-catalyzed reaction of 3-aryl-2-chlorothiophenes with some aromatic ethers unexpectedly led to the formation of the corresponding 2,4-isomers.
