کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1257683 | 971576 | 2011 | 4 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Highly active bifunctional salenTi(IV) catalysts for asymmetric cyanosilylation of aldehydes and TMSCN Highly active bifunctional salenTi(IV) catalysts for asymmetric cyanosilylation of aldehydes and TMSCN](/preview/png/1257683.png)
A novel enantiopure salen ligand bearing a diphenylphosphine oxide on the 3-position of one aromatic ring was synthesized and combined with Ti(Oi-Pr)4 as a monometallic bifunctional catalyst for asymmetric cyanosilylation reaction of aldehydes with trimethylsilyl cyanide (TMSCN). The catalyst system exhibited excellent activity and moderate enantioselectivity. The addition of TMSCN to 4-nitrobenzaldehyde in the presence of 1 mol% catalyst loading could complete within 10 min at ambient temperature. An intramolecularly cooperative catalysis was observed in this system wherein the central metal Ti(IV) is suggested to play a role of Lewis acid to activate aldehydes while the appended diphenylphosphine oxide worked as Lewis base to activate TMSCN.
Journal: Chinese Chemical Letters - Volume 22, Issue 11, November 2011, Pages 1285–1288