The rhodium(I)-catalyzed reaction of alkynes with formaldehyde proceeds via the double incorporation of a carbonyl moiety from formaldehyde, resulting in a CO gas-free cyclohydrocarbonylation leading to α,β-butenolides.
The Reaction of α-Diazo-β-hydroxy Esters with Boron Trifluoride Etherate: Generation and Rearrangement of Destabilized Vinyl Cations. A Detailed Experimental and Theoretical Study
作者:Roberto Pellicciari、Benedetto Natalini、Bahman M. Sadeghpour、Maura Marinozzi、James P. Snyder、Bobby L. Williamson、Jeffrey T. Kuethe、Albert Padwa
DOI:10.1021/ja950971s
日期:1996.1.1
ketones. Further treatment of these α-diazo-β-hydroxy esters with boron trifluoride etherate in various solvents affords an unusual array of products. Product types and ratios were found to be strongly dependent on ringsize and the solvent used. The reaction proceeds by Lewis acid complexation of the alcohol functionality of the diazo hydroxy ester with BF3 etherate followed by neighboring-group participation
Cu(II)-Catalyzed Acylation by Thiol Esters Under Neutral Conditions: Tandem Acylation-Wittig Reaction Leading to a One-Pot Synthesis of Butenolides
作者:Kazumasa Matsuo、Mitsuru Shindo
DOI:10.1021/ol102407k
日期:2010.11.19
The first catalytic acylation of alcohols with a thiolester present in Wittig reagents under neutral conditions catalyzed by the Cu(II) salt through a push−pull mechanism is reported. Furthermore, a new methodology for the one-pot lactonization of acyloins by a copper catalyst is developed. The synthetic utility of this method for the synthesis of natural products is shown.
Gold-Catalyzed Cascade Oxidative Cyclization and Arylation of Allenoates
作者:Rui Zhang、Qin Xu、Kai Chen、Peng Gu、Min Shi
DOI:10.1002/ejoc.201300896
日期:2013.11
was found to be effective for the cascadeoxidativearylation and cyclization of allenoates with arylboronic acids to give the corresponding cyclic adducts in moderate yields. This reaction system constitutes a new method for the synthesis of β-aryl-γ-butenolides under mild conditions. Based on the previous mechanistic studies, a proposed AuI/AuIII redox catalytic cycle has been outlined.