704-79-0Relevant articles and documents
Synergistic N-Heterocyclic Carbene/Palladium-Catalyzed [3 + 2] Annulation of Vinyl Enolates with 1-Tosyl-2-vinylaziridine
Gao, Jian,Zhang, Jianming,Fang, Shuaishuai,Feng, Jie,Lu, Tao,Du, Ding
, p. 7725 - 7729 (2020/10/09)
The synergistic combination of N-heterocyclic carbene organocatalysis and transition-metal catalysis for a formal [3 + 2] annulation between 3-substituted but-2-enoates and 1-tosyl-2-vinylaziridine was developed. This cooperative strategy provides a facile and efficient access to various functionalized (E)-3-ethylidene-4-vinylpyrrolidin-2-ones in a regioselective and stereoselective manner. The preliminary asymmetric studies were also performed, which indicated a potential for enantioselective annulation of vinyl enolate intermediates with transition-metal-π-allyl species.
Synthesis of 6-hydroxy-5,6-dihydro-2-pyrones and -pyridones by reaction of 4-aryl-6-trifluoromethyl-2-pyrones with water, hydrazine, and hydroxylamine
Usachev, Sergey A.,Usachev, Boris I.,Sosnovskikh, Vyacheslav Ya.
, p. 1294 - 1301 (2018/01/27)
[Figure not available: see fulltext.] Reactions of 4-aryl-6-trifluoromethyl-2H-pyran-2-ones with sodium hydroxide followed by acidification provided the respective 6-hydroxy-5,6-dihydro derivatives, while the reactions of 4-aryl-6-trifluoromethyl-2H-pyran
One Photocatalyst, n Activation Modes Strategy for Cascade Catalysis: Emulating Coumarin Biosynthesis with (-)-Riboflavin
Metternich, Jan B.,Gilmour, Ryan
, p. 1040 - 1045 (2016/02/05)
Generating molecular complexity using a single catalyst, where the requisite activation modes are sequentially exploited as the reaction proceeds, is an attractive guiding principle in synthesis. This requires that each substrate transposition exposes a catalyst activation mode (AM) to which all preceding or future intermediates are resistant. While this concept is exemplified by MacMillan's beautiful merger of enamine and iminium ion activation, examples in other fields of contemporary catalysis remain elusive. Herein, we extend this tactic to organic photochemistry. By harnessing the two discrete photochemical activation modes of (-)-riboflavin, it is possible to sequentially induce isomerization and cyclization by energy transfer (ET) and single-electron transfer (SET) activation pathways, respectively. This catalytic approach has been utilized to emulate the coumarin biosynthesis pathway, which features a key photochemical E → Z isomerization step. Since the ensuing SET-based cyclization eliminates the need for a prefunctionalized aryl ring, this constitutes a novel disconnection of a pharmaceutically important scaffold.
