Novel chiral (salen)Mn(<scp>iii</scp>) complexes containing a calix[4]arene unit in 1,3-alternate conformation as catalysts for enantioselective epoxidation reactions of (Z)-aryl alkenes
作者:Carmela Bonaccorso、Giovanna Brancatelli、Francesco P. Ballistreri、Silvano Geremia、Andrea Pappalardo、Gaetano A. Tomaselli、Rosa M. Toscano、Domenico Sciotto
DOI:10.1039/c3dt52550c
日期:——
Two new chiral calix[4]arene-salen ligands 1a,b, based on calix[4]arene platforms in 1,3-alternate conformation, have been prepared by a new general synthetic pathway. Their Mn(III) complexes, 3a,b, have shown fairly good efficiency in the asymmetric epoxidation of styrene and substituted styrenes, whereas excellent catalytic activity and selectivity were observed with rigid bicyclic alkenes, namely
通过新的一般合成途径,制备了基于1,3-交替构象的杯[4]亚芳基平台的两个新的手性杯[4]亚芳-salen配体1a,b。它们的Mn(III)配合物3a,b在苯乙烯和取代的苯乙烯的不对称环氧化中显示出相当好的效率,而在刚性双环烯烃(即1,2-二氢萘和取代的2)上观察到优异的催化活性和选择性。 ,2'-二甲基色烯。3a的较高催化性能可能归因于结构相似的UO 2络合物2a,b的分子建模,NMR光谱和X射线数据证明,具有更高的刚性和固有的手性结构。