Isocyanide-Based Multicomponent Reaction To Furnish N-Functionalized Indoles by using <i>N</i>
-Acyliminium Ions as Key Intermediates
作者:Guangsheng Cheng、Hongmei Deng、Xiang He、Yu Gao、Chunju Li、Xueshun Jia、Jian Li
DOI:10.1002/ejoc.201700826
日期:2017.8.17
The present work discloses an efficient multicomponent reaction of isocyanide, allenoate, and indole. In the absence of any catalyst, this protocol provides a rapid and direct access to furnish N-H functionalization of indole from readily available starting materials. This strategy also features the broad substrate scope and mild conditions.
Platinum-Catalyzed Intramolecular Hydroarylation of Allenyl Arenes: Efficient Synthesis of 1,4-Dihydronaphthalenes
作者:Juntae Mo、Phil Ho Lee
DOI:10.1021/ol1007857
日期:2010.6.4
An efficient synthetic method of 1,4-dihydronaphthalenes having various alkyl groups on the 4-position and/or ethoxycarbonyl group on the 2-position through selective intramolecular Pt-catalyzed 6-endo cyclohydroarylation of ethyl 2-benzyl-2,3-alkadienoates was developed. The present method could be further extended to two-fold Pt-catalyzed 6-endo and 7-endo cyclizations.
The thermal [3 + 2] cycloaddition reaction of N-iminoquiazoline ylides with allenoates worked efficiently under mild reaction conditions to provide a variety of tetrahydropyrazoloquinazoline derivatives in good to excellent yields and moderate to excellent diastereoselectivities.
Phosphine-Catalyzed [4 + 2] Annulation: Synthesis of Cyclohexenes
作者:Yang S. Tran、Ohyun Kwon
DOI:10.1021/ja0752181
日期:2007.10.1
Phosphine-catalyzed [4 + 2] annulations of α-alkylallenoates with activated olefins allow the efficient syntheses of cyclohexenes. Hexamethylphosphorous triamide (HMPT)-catalyzed [4 + 2] annulations of α-alkylallenoates with arylidenemalononitriles provided highly functionalized 5,5-dicyano-4,6-disubstituted cyclohex-1-enecarboxylates in excellent yields (77−98%) and moderate to high diastereoselectivities
phosphine as the catalyst, the first catalytic enantioselective [4 + 3] annulation of allenoates with C,N-cyclic azomethine imines is developed. The reaction works efficiently under mild reaction conditions to afford seven-membered ring-fused quinazoline-based tricyclic heterocycles in high yields with good to excellent diastereo- and enantioselectivities.