DDQ-Mediated Oxidative Coupling: An Approach to 2,3-Dicyanofuran (Thiophene)
摘要:
A facile oxidative coupling of alpha-carbonyl radicals to 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) for the synthesis of 2,3-dicyanofurans and thiophenes starting from readily available beta-diketones, simple ketones, and beta-keto thioamides in up to 95% yield in one step was developed. Mechanistic investigations revealed that a radical process could be involved in this transformation, and a water promoted C-C bond cleavage pathway is proposed for the formation of 2,3-dicyanofurans and thiophenes.
Regioselective Metal-Free One-Pot Synthesis of Functionalized 2-Aminothiophene Derivatives
作者:Xiaoyan Luo、Li-Shi Ge、Xing-Lan An、Jing-Hai Jin、Yu Wang、Pei-Pei Sun、Wei-Ping Deng
DOI:10.1021/acs.joc.5b00488
日期:2015.5.1
A facile metal-free synthesis of 2-aminothiophene derivatives by the reaction of 2-ynals with thioamides in alcohols has been developed. This transformation allows the assembly of 2-aminothienyl ether derivatives via a well-designed aldol condensation/regioselective intramolecular cyclization/conjugateaddition cascade reaction and provides a straightforward synthetic protocol for constructing 2,3
Cu(II)-catalyzed one-pot synthesis of fully substituted dihydrothiophenes and thiophenes from thioamides and enynones
作者:Min Wen、Pei-Pei Sun、Xiaoyan Luo、Wei-Ping Deng
DOI:10.1016/j.tet.2018.02.035
日期:2018.8
developed for the construction of fully substituted dihydrothiophenes, which via a copper-catalyzed Michael addition/intramolecular cyclization/protonation cascadereaction of readily available thioamides with enynones under air atmosphere. This approach provides 2,3-dihydrothiophenes with up to 92% yield in a one-pot process. In addition, several fully substituted thiophenes could also be synthesized
Synthesis of Polysubstituted 3-Aminothiophenes from Thioamides and Allenes via Tandem Thio-Michael Addition/Oxidative Annulation and 1,2-Sulfur Migration
作者:Teng Han、Yu Wang、Hong-Liang Li、Xiaoyan Luo、Wei-Ping Deng
DOI:10.1021/acs.joc.7b02616
日期:2018.2.2
A facile synthetic method for the construction of 3-aminothiophenes from readily available thioamides and alllenes in the presence of a TBAI/TBHP catalyst system was developed. This protocol represents an efficient and straightforward way to access highly functionalized thiophenes in moderate to excellent yields under mild conditions, via a tandem thio-Michael addition, oxidative annulation, and 1
Optically Active Thiophenes via an Organocatalytic One-Pot Methodology
作者:Lars Krogager Ransborg、Łukasz Albrecht、Christian F. Weise、Jesper R. Bak、Karl Anker Jørgensen
DOI:10.1021/ol203237r
日期:2012.2.3
A general methodology for the synthesis of trisubstituted, optically active thiophenes by an organocatalytic one-pot reaction cascade is presented. The target products are synthesized in good yields (up to 92%) and with excellent enantioselectivities (up to 98% ee). Importantly, based on practical and easily available starting materials, the presented methodology can be conducted under mild reaction conditions. To further elucidate the generality, the synthesis of optically active thienoindoles, as well as selenophenes, is also demonstrated.