A highly enantioselective cyano-phosphorylation of aldehydes catalyzed by a YLi(3)tris(binaphtlioxide) complex YLB 1 is described. The slow addition of diethyl cyanophosphonate 4 to aldehydes 5 in the presence of YLB 1 (10 mol %), H2O (30 mol %), tris(2,6-dimethoxyplienyl)phosphine oxide 3a (10 mol %), and BuLi (10 mol %) afforded cyanohydrin O-phosphates 6 in up to 98% yield and 97% ee. Mechanistic studies revealed that the addition of cyanide to aldehydes is irreversible and determines the enantioselectivity. The reaction mechanism is also discussed in detail. (c) 2006 Elsevier Ltd. All rights reserved.
Enantioselective Synthesis of Cyanohydrin O-Phosphates Mediated by the Bifunctional Catalyst Binolam–AlCl
作者:Alejandro Baeza、Jesús Casas、Carmen Nájera、José M. Sansano、José M. Saá
DOI:10.1002/anie.200351552
日期:2003.7.14
Binolam-AlCl: A Two-Centre Catalyst for the Synthesis of Enantioenriched CyanohydrinO-Phosphates
作者:Alejandro Baeza、Carmen Nájera、José M. Sansano、José M. Saá
DOI:10.1002/chem.200401290
日期:2005.6.20
The enantioselectivesynthesis of cyanohydrinO-phosphates by using in situ generated bifunctionalcatalysts (R)- or (S)-3,3'-bis(diethylaminomethyl)-1,1'-binaphthol-aluminium chloride (binolam-AlCl) is reported. The reaction, which can be described as an overall cyano-O-phosphorylation of aldehydes, has a wide scope and applicability. Evidence is also provided, including ab initio and DFT calculations