192586-59-7Relevant academic research and scientific papers
Lewis Acid Catalyzed Electrophilic Aminomethyloxygenative Cyclization of Alkynols with N, O-Aminals
Chen, Anrong,Yu, Houjian,Yan, Jiaqi,Huang, Hanmin
, p. 755 - 759 (2020/01/28)
Lewis acid enables the electrophilic carbooxygenative cyclization of alkynols with N,O-aminals. The new process proceeds efficiently under very mild conditions via a pathway that is opposite to classical carbo-metalation. These reactions exhibit broad substrate generality and functional group compatibility, leading to a wide variety of 5-8-membered oxacycles bearing diverse functional groups. The cyclization products can be elaborated via simple functional group transformations to generate synthetically useful oxacycles.
Yttrium-Catalyzed Intramolecular Hydroalkoxylation/Claisen Rearrangement Sequence: Efficient Synthesis of Medium-Sized Lactams
Zhou, Bo,Li, Long,Zhu, Xin-Qi,Yan, Juan-Zhu,Guo, Yi-Lin,Ye, Long-Wu
supporting information, p. 4015 - 4019 (2017/03/27)
An efficient yttrium-catalyzed intramolecular hydroalkoxylation/Claisen rearrangement sequence has been achieved, thus enabling facile access to a diverse array of valuable medium-sized lactams. Furthermore, a mechanistic rationale for this novel cascade
Nucleophilic cycloaromatization of ynamide-terminated enediynes
Poloukhtine, Andrei,Rassadin, Valentin,Kuzmin, Alexander,Popik, Vladimir V.
supporting information; experimental part, p. 5953 - 5962 (2010/11/05)
Introduction of a nitrogen atom at one of the acetylenic termini of 10-, 11-, 12-, and 13-membered benzannulated cyclic enediynes results in a complete suppression of the conventional radical Bergman reaction in favor of a polar cycloaromatization. The latter reaction is catalyzed by acids and proceeds via initial protonation of an ynamide fragment. The resulting ketenimmonium cation then cyclizes to produce naphthyl cation, which rapidly reacts with nucleophiles or undergoes Friedel-Crafts addition to aromatic compounds. In alcohols, addition of the nucleophilic solvent across the activated triple bond competes with the cyclization reaction. The ratio of cyclized to solvolysis products decreases with the increase in ring size.
