tris(alkoxycarbonyl) olefins 2 or 1,1-bis(alkoxycarbonyl)-2-acyl olefins 3 in the presence of ZnBr(2) at -30 degrees C gave cis-substituted cyclopropanes exclusively. The origin of the cis stereochemistry is ascribed to the synclinal addition path of the ZnBr(2)-coordinated electrophilic olefin to 1. Application of the highly functionalized selenium- and silicon-substituted cyclopropane products to the preparation
Indenes are important core structures in organic chemistry. Few simple arylallenes have been used to construct indene skeletons by Friedel Crafts reaction. Lewis acid catalyzed reaction of ethenetricarboxylates 1 and arylallenes has been examined in this study. The reaction of arylallenes and ethenetricarboxylate triesters with SnCl4 gave indene derivatives efficiently, via a conjugate addition/Friedel-Crafts cyclization reaction. On the other hand, the reactions of 1,1-diethyl 2-hydrogen ethenetricarboxylate and arylallenes or alkylallenes with SnCl4 at -78 degrees C or room temperature and subsequent treatment with Et3N gave gamma-lactones. The reactions of triethyl ethenetricarboxylate and 1,1-dialkylallenes with SnCl4 at room temperature also gave gamma-lactones.
Pd-catalyzed one-pot coupling of allylamines, activated alkenes, and unsaturated halides (or triflate): an atom efficient synthesis of highly functionalized pyrrolidines
作者:Luc Martinon、Stéphane Azoulay、Nuno Monteiro、E. Peter Kündig、Geneviève Balme
DOI:10.1016/j.jorganchem.2004.07.039
日期:2004.11
A Pd-catalyzed three-component assembling of highly functionalized 4-benzyl-(and allyl-)pyrrolidines was achieved based on a combination of allyl amines, gem-diactivated alkenes, and unsaturated halides (or triflate). (C) 2004 Elsevier B.V. All rights reserved.
OUALI M. S.; VAULTIER M.; CARRIE R., BULL. SOC. CHIM. FRANCE, 1979, PART 2, NO 11-12, 633-643