carried out in order to investigate the stability of related structures. The PNNP ligands 2 and 3 in combination with Fe3(CO)12 as iron source were tested as catalysts in the asymmetric transfer hydrogenation of a variety of ketones with conversions higher than 95 % and enantioselectivities up to 97 %.
                                    PNNP
配体(R,R)-PPh 2(2-C 6 H 4)CH = N(
吡咯烷-NBn)-} 2 2是通过2-
二苯基膦基苯甲醛与
吡咯烷取代的二胺1缩合制备的。用MeOH中的NaBH 4还原得到(R,R)-PPh 2(2-C 6 H 4)CH-NH(
吡咯烷-NBn)-} 2 3。相应的
铁(II)配合物[FeCl 2(2)](4),[Fe(CH 3 CN)2(合成了2)](BF 4)2(5)和[Fe(CH 3 CN)2(2)](PF 6)2(6),并通过NMR,ESI-HRMS和EA进行了全面表征。为了研究相关结构的稳定性,对[FeCl 2(2)](4)和[Fe(CH 3 CN)2(2)](BF 4)2(5)进行了DFT计算。
PNNP
配体2和3与
铁结合在各种酮的不对称转移氢化中,以3(CO)12作为
铁源作为催化剂进行了测试,转化率高于95%,对映选择性高达97%。