An X<sup>-</sup> (X = I, Br)-Triggered Ring-Opening Coupling Reaction of Cyclopropenes with Organic Halides
作者:Shengming Ma、Junliang Zhang、Yangjun Cai、Lianghua Lu
DOI:10.1021/ja038131y
日期:2003.11.1
Polyfunctionalized (E)-alk-1-enyl halides 3 were efficiently synthesized in high yields via a novel regio- and stereoselective X- (X = I or Br)-triggered ring-opening couplingreaction of cyclopropenes 1 with organic halides 2.
A triazole-templated ring-closing metathesis for constructing novel fused and bridged triazoles
作者:Xuejun Zhang、Richard P. Hsung、Hongyan Li
DOI:10.1039/b701040k
日期:——
The feasibility of trapping the vinyl copper intermediate generated in situ from azide-[3 + 2] cycloadditions and viability of employing these triazoles as unique templates for ring-closing metathesis are described here; this work effectively combines the two powerful reactions for the first time to construct various de novo fused and bridged triazoles that are otherwise not trivial to synthesize.
Theoretical Support for the Involvement of a Radical Pathway in the Formation of Allenylzincs from Propargyl Iodides and Dialkylzincs: Influence of Zinc Coordination
作者:Suribabu Jammi、Dominique Mouysset、Didier Siri、Michèle P. Bertrand、Laurence Feray
DOI:10.1021/jo302704g
日期:2013.2.15
undergo homolytic substitution at zinc. The stabilization of allenylzinc derivatives by chelation, made possible by the selection of appropriate ortho-substituted 3-phenylalkynyl iodides as precursors, was shown to influence the regioselectivity of their addition to aldehydes and ketones. The more stabilized the chelated allenylzinc intermediate, the higher the ratio of homopropargylic alcohols.
An optimized ligand‐controlled palladium‐catalyzed allenesynthesis starting fromalkynes and arylbromides giving rise to allene products in a simple and direct manner is described. The methodology is performed in an inter‐ and intramolecular fashion with unprecedented scope and excellent yields. Based on mechanistic investigations and on DFT calculations, the role played by the carboxylic additive
I–-Catalyzed Reaction of 5-Methoxyoxazoles with Organic Iodides – An Efficient Synthesis of Azalactones
作者:Lianghua Lu、Ping Lu、Shengming Ma
DOI:10.1002/ejoc.200600637
日期:2007.2
An I–-catalyzed methoxy carbon–oxygen bond cleavage in 5-methoxyoxazoles leading to the synthesis of azalactones, precursors of quaternary amino acids, has been developed. A series of 4-substituted azalactones were obtained through the variation of the alkyl iodides and differently substituted 5-methoxyoxazoles. Further study indicated that azalactone 3aa may be easily converted to benzoyl-protected