|
| ||
|
|
||
Catalytic Asymmetric Mannich-Type Reaction (catalytic + asymmetric_mannich-type_reaction)
Selected AbstractsChemInform Abstract: Direct Catalytic Asymmetric Mannich-Type Reaction of ,-Keto Phosphonate Using a Dinuclear Ni2,Schiff Base Complex.CHEMINFORM, Issue 47 2008Zhihua Chen Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] A Direct Catalytic Asymmetric Mannich-Type Reaction via a Dinuclear Zinc Catalyst: Synthesis of Either anti- or syn-,-Hydroxy-,-amino Ketones.CHEMINFORM, Issue 28 2006Barry M. Trost Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Direct Catalytic Asymmetric Mannich-Type Reaction of Hydroxyketone Using a Et2Zn/Linked-BINOL Complex: Synthesis of Either anti- or syn-,-Amino Alcohols.CHEMINFORM, Issue 46 2004Shigeki Matsunaga Abstract For Abstract see ChemInform Abstract in Full Text. [source] Catalytic Asymmetric Mannich-Type Reactions Activated by ZnF2 Chiral Diamine in Aqueous Media.CHEMINFORM, Issue 16 2006Tomoaki Hamada Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] PdII -Catalyzed Asymmetric Addition Reactions of 1,3-Dicarbonyl Compounds: Mannich-Type Reactions with N -Boc Imines and Three-Component AminomethylationCHEMISTRY - AN ASIAN JOURNAL, Issue 8-9 2008Yoshitaka Hamashima Dr. Abstract This paper describes catalytic asymmetric Mannich-type reactions of ,-ketoesters and malonates using chiral palladium complexes. Although readily enolizable, carbonyl compounds are attractive substrates, the use of such compounds as nucleophiles in Mannich-type reactions has not been extensively investigated. In the presence of chiral Pd aqua complexes (2.5,mol,%), ,-ketoesters reacted with various N -Boc imines (Boc=tert -butoxycarbonyl) to afford the desired ,-aminocarbonyl compounds in good yield with high to excellent stereoselectivity (up to 96:4 d.r., 95,99,%,ee in most cases). In these reactions, construction of highly crowded vicinal quaternary and tertiary carbon centers was achieved in one step. A chiral Pd enolate is considered to be the key intermediate. To elucidate the stereoselectivity observed in the reaction, possible transition-state models are discussed, taking into account steric and stereoelectronic effects. Furthermore, this catalytic system was applied to the Mannich-type reaction of malonates with N -Boc imine as well as one-pot classical aminomethylation of ,-ketoesters using benzylamine salt and formalin. The reactions proceeded smoothly, and the corresponding Mannich products were obtained in high yield with moderate to good enantioselectivity. [source] | ||||||||||