Use of 1,3-Dioxin-4-ones and Related Compounds in Synthesis. XLIV. Asymmetric Aldol Reaction of 4-Trimethylsiloxy-6-methylene-1,3-dioxines: Use of Tartaric Acid-Derived (Acyloxy)borane Complex as the Catalyst.
Lewis Base Activation of Lewis Acids: Catalytic, Enantioselective Addition of Silyl Ketene Acetals to Aldehydes
作者:Scott E. Denmark、Gregory L. Beutner、Thomas Wynn、Martin D. Eastgate
DOI:10.1021/ja047339w
日期:2005.3.1
The concept of Lewisbase activation of Lewisacids has been reduced to practice for catalysis of the aldolreaction of silyl ketene acetals and silyl dienol ethers with aldehydes. The weakly acidic species, silicon tetrachloride (SiCl4), can be activated by binding of a strongly Lewis basic chiral phosphoramide, leading to in situ formation of a chiral Lewisacid. This species has proven to be a competent
Apparent Catalytic Generation of Chiral Metal Enolates: Enantioselective Dienolate Additions to Aldehydes Mediated by Tol-BINAP·Cu(II) Fluoride Complexes
作者:Jochen Krüger、Erick M. Carreira
DOI:10.1021/ja973331t
日期:1998.2.1
To Probe the Origin of Activation Effect of Carboxylic Acid and (+)-NLE in Tridentated Titanium Catalyst Systems
作者:Yu Yuan、Xin Li、Jie Sun、Kuiling Ding
DOI:10.1021/ja0286775
日期:2002.12.1
The activation effect of carboxylic acid and positive nonlinear effect ((+)-NLE) in tridentated titanium catalyst systems for hetero Diels-Alder reaction and aldol-type reactions has been first elucidated on the basis of X-ray crystal structural analysis of homochiral (pseudo-octahedral coordination geometry with C2 symmetry) and heterochiral (pseudo-octahedral coordination geometry with C1 symmetry) titanium complexes and the observation of their different reactivities with carboxylic acid additive.
Catalytic, Enantioselective Dienolate Additions to Aldehydes: Preparation of Optically Active Acetoacetate Aldol Adducts
作者:Robert A. Singer、Erick M. Carreira
DOI:10.1021/ja00154a049
日期:1995.12
Sato Masayuki, Sunami Satoshi, Sugita Yoshiaki, Kaneko Chikara, Chem. and Pharm. Bull, 42 (1994) N 4, S 839-845