81344-85-6Relevant academic research and scientific papers
Cu-Catalyzed Dehydrogenative C-O Cyclization for the Synthesis of Furan-Fused Thienoacenes
Mitsudo, Koichi,Kobashi, Yoshiaki,Nakata, Kaito,Kurimoto, Yuji,Sato, Eisuke,Mandai, Hiroki,Suga, Seiji
, p. 4322 - 4326 (2021)
The first Cu-catalyzed dehydrogenative C-O cyclization for the synthesis of furan-fused thienoacenes is described. A variety of heteroacenes including a thieno[3,2-b]furan or a thieno[2,3-b]furan skeleton were synthesized by intramolecular C-H/O-H coupling. The use of a mixed solvent of N-methyl-2-pyrrolidone, ethylene glycol monomethyl ether, and toluene was essential for suppressing side reactions and efficiently promoting the reaction. Double C-O cyclization was also conducted to afford highly π-expanded furan-fused thienoacenes.
Rhodium-catalyzed ortho-heteroarylation of phenols: directing group-enabled switching of the electronic bias for heteroaromatic coupling partner
Wu, Yimin,Li, Wei,Jiang, Linfeng,Zhang, Luoqiang,Lan, Jingbo,You, Jingsong
, p. 6878 - 6882 (2018/09/11)
The directed oxidative C-H/C-H cross-coupling reactions between a functionalized arene and a heteroarene typically exhibit an electronic bias for the heteroaromatic coupling partner. Disclosed herein is a conception of directing group enabled-switching of the electronic bias for coupling partner from the electron-deficient to electron-rich heteroarene, demonstrating that the modification of the directing group may match the latent reactivity of heteroarene substrates caused by the distinctly different electronic nature. In this work, we develop a Rh(iii)-catalyzed ortho-heteroarylation of phenols with greatly important electron-rich heteroarenes such as benzothiophene, benzofuran, thiophene, furan and pyrrole via two-fold C-H activation, which presents broad substrate scopes of both phenols and electron-rich heteroarenes and shows the advantage of tolerance of reactive functional groups, especially halogen. This work also provides a new strategy for the construction of π-conjugated furan-fused heteroacenes prevalent in materials science in dramatically simplified procedures, which makes the protocol highly applicable.
p-Toluenesulfonic acid-promoted selective functionalization of unsymmetrical arylalkynes: a regioselective access to various arylketones and heterocycles
Jacubert, Maud,Provot, Olivier,Peyrat, Jean-Fran?ois,Hamze, Abdallah,Brion, Jean-Daniel,Alami, Mouad
experimental part, p. 3775 - 3787 (2010/07/04)
Regioselective hydration of a wide range of internal alkynes has been afforded in high to good yields by using PTSA in EtOH. The scope of the reaction of alkynes has been delineated. Arylaliphatic alkynes and diarylalkynes were regioselectively hydrated in good to excellent yields and short reaction times when the reaction was achieved under microwave irradiation. Moreover, diarylalkynes, arylenynes as well as diaryldiynes bearing a methoxy- or a thiomethyl substituent on the ortho position underwent a regioselective 5-endo-dig-cyclization to give a variety of 2-aryl- and 2-styrylbenzofuran or benzothiphene derivatives. We believe that, this new environmentally metal-free procedure combined to microwave irradiation would be in importance in the search of green laboratory-scale synthesis.
p-Toluenesulfonic acid-mediated cyclization of o-(1-alkynyl)anisoles or thioanisoles: synthesis of 2-arylsubstituted benzofurans and benzothiophenes
Jacubert, Maud,Hamze, Abdallah,Provot, Olivier,Peyrat, Jean-Fran?ois,Brion, Jean-Daniel,Alami, Mouad
experimental part, p. 3588 - 3592 (2009/09/28)
A variety of 2-arylbenzo[b]furans are readily prepared in good to excellent yields from the cyclization of o-(1-alkynyl)anisole derivatives under mild reaction conditions using an alcoholic media, p-toluenesulfonic acid under microwave irradiation. Starti
