Ruthenium Catalyzed Decarbonylative Arylation at sp<sup>3</sup> Carbon Centers in Pyrrolidine and Piperidine Heterocycles
作者:Denis V. Gribkov、Stefan J. Pastine、Michael Schnürch、Dalibor Sames
DOI:10.1021/ja072577n
日期:2007.9.1
ruthenium-catalyzed decarbonylative arylation of cyclic 2-amino esters, which replaces the ester group with an aryl ring at the sp3 carbon center. For example, proline ester amidine 1 is converted to 2-arylpyrrolidine 3 in the presence of arylboronic acids or esters as arene donors and Ru(3)(CO)(12) as the catalyst. This process provides a rapid access to a variety of 2-arylpyrrolidines and piperidines from
C1-Symmetric VersusC2-Symmetric Ligands in Enantioselective Copper–Bis(oxazoline)-Catalyzed Cyclopropanation Reactions
作者:José M Fraile、José I. García、Anja Gissibl、José A. Mayoral、Elísabet Pires、Oliver Reiser、Marta Roldán、Isabel Villalba
DOI:10.1002/chem.200700681
日期:2007.10.26
A thorough experimental and theoretical study of the enantioselective cyclopropanation of alkenes catalyzed by chiralbis(oxazoline)- and azabis(oxazoline)-copper complexes, which comprise a new family of ligands that lack C2 symmetry, has been conducted. Surprisingly high enantioselectivities were observed with some of these ligands, which were rationalized on the basis of molecular modeling studies