Michael Additions Involving Amino Acid Esters with Alkenyl N-Heterocycles
作者:Sean H. Kennedy、Douglas A. Klumpp
DOI:10.1021/acs.joc.7b01724
日期:2017.10.6
variety of aminoacidesters and 2- or 4-vinylpyridine. Similar reactions were accomplished with an alkenyl-substituted pyrimidine, pyrazine, thiazole, quinoxaline, benzoxazole, and quinolone. In reactions at a prochiral center, modest diastereoselectivities were observed with the formation of the new stereogenic carbon. NMR experiments indicate that the addition reaction is reversible under acidic conditions
The diastereo- and enantioselective reductive coupling of vinylazaarenes with N-Boc aldimines is described, The reactions proceed using chiral copper-bisphosphine complexes in the presence of TMOS as a hydride source to give reductive coupling products in moderate to high enantioselectivities.
Enantioselective Copper-Catalyzed Reductive Coupling of Alkenylazaarenes with Ketones
作者:Aakarsh Saxena、Bonnie Choi、Hon Wai Lam
DOI:10.1021/ja3036916
日期:2012.5.23
Catalytic enantioselective methods for the preparation of chiral azaarene-containing compounds are of high value. By combining the utility of copper hydride catalysis with the ability of C=N-containing azaarenes to activate adjacent alkenes toward nucleophilic additions, the enantioselective reductive coupling of alkenylazaarenes with ketones has been developed. The process is tolerant of a wide variety of azaarenes and ketones, and provides aromatic heterocycles bearing tertiary-alcohol-containing side chains with high levels of diastereo- and enantioselection.