New and mildconditions to prepare chiral bicyclic lactams in high yields and high diastereoselectivities are reported herein. This approach based on the activation of the carboxylic acid by means of Mukaiyama’s reagent is an excellent alternative to Meyers’ dehydrating conditions and provide the main advantage to work at lower temperature (40 °C). Higher diastereoselectivity was obtained with 5,7-bicyclic
Various thiolesters are prepared in good yields by the reaction of thiols with acyloxypyridinium salts formed in situ from free carboxylic acids and 2-fluoro-1-methylpyridinium p-toluenesulfonate.
KULINKOVICH, O. G.;TISHCHENKO, I. G.;ROSLIK, N. A., SYNTHESIS, BRD, 1982, N 11, 931-933
作者:KULINKOVICH, O. G.、TISHCHENKO, I. G.、ROSLIK, N. A.
DOI:——
日期:——
Pd-catalyzed Fukuyama cross-coupling of secondary organozinc reagents for the direct synthesis of unsymmetrical ketones
作者:Alan H. Cherney、Sarah E. Reisman
DOI:10.1016/j.tet.2013.11.104
日期:2014.5
organometallic reagents represents a convergent route toward complex and versatile ketone products. Despite the mild conditions and high functional group tolerance, the cross-coupling of carboxylic acid derivatives, such as thioesters, and secondary organometallic reagents is an underdeveloped transformation. Herein, we disclose a convenient and efficient protocol for the Pd-catalyzed Fukuyama cross-coupling