Enantioselective hydrophosphonylation of N - benzyl imines, isatin derived ketimines and isatins catalyzed by in-situ generated Ti(IV) macrocyclic salen complexes
作者:Mohd Nazish、Ajay Jakhar、Noor-ul H. Khan、Shailesh Verma、Rukhsana I. Kureshy、Sayed H.R. Abdi、Hari C. Bajaj
DOI:10.1016/j.apcata.2015.12.037
日期:2016.4
benzylimines, whereas for ketimines diphenyl phosphite (IIb) gave best results with very good yield (up to 88%) and ee (up to 99%). The Ti(IV) complex was recoverable and recyclable with retention of its catalytic performance at gram scale level. To understand the reaction mechanism NMR studies have been carried out using benzylimine as a model substrate and dimethyl phosphite as a nucleophile.
Ti-salen配合物是通过使用一系列手性大环Salen配体生成的,并用作苄亚胺,靛红衍生的酮亚胺和靛红的对映选择性氢膦酰化(EHP)反应的催化剂。使用亚磷酸二甲酯作为亲核试剂(IIa),对于靛红和苄基亚胺,而对于酮亚胺二亚磷酸亚砜(b)以非常好的收率(高达88%)和ee(高达99%)给出了最佳结果。Ti(IV)配合物可回收并可回收,并且其催化性能保持在克级。为了理解反应机理,已经使用苄基亚胺作为模型底物和亚磷酸二甲酯作为亲核试剂进行了NMR研究。