Studies aimed at enhancement of reactivity and enantioselectivity of a lithium ester enolate using a chiral tridentate lithium amide
作者:Mostafa Ahmed Hussein、Akira Iida、Kiyoshi Tomioka
DOI:10.1016/s0040-4020(99)00644-4
日期:1999.9
chiral amines 7–13 mediated the asymmetric condensation reaction of lithium ester enolate 2 with benzaldehyde p-anisidine imine 3 giving the corresponding β-lactam 4 in up to 75% ee. It became apparent that coexistence of 2 and chiral lithium amides derived from 7–13 is an important factor for the enhancement of the reactivity and enantioselectivity of 2.
Chiral Amino Ether-Controlled Catalytic Enantioselective Arylthiol Conjugate Additions to α,β-Unsaturated Esters and Ketones: Scope, Structural Requirements, and Mechanistic Implications
作者:Katsumi Nishimura、Kiyoshi Tomioka
DOI:10.1021/jo015879v
日期:2002.1.1
Asymmetric conjugate addition reaction of 2-trimethylsilylbenzenethiol with enoates and enones is catalyzed by a chiral amino ether-lithium thiolate complex and affords adducts with high enantioselectivity. Both the s-cis conformation and a steric wall at one side of the carbonyl group are structural requirements in substrates yielding adducts with high enantioselectivity. Reactions with tert-butyl
Hydrogen Bonding Phase-Transfer Catalysis with Potassium Fluoride: Enantioselective Synthesis of β-Fluoroamines
作者:Gabriele Pupo、Anna Chiara Vicini、David M. H. Ascough、Francesco Ibba、Kirsten E. Christensen、Amber L. Thompson、John M. Brown、Robert S. Paton、Véronique Gouverneur
DOI:10.1021/jacs.8b12568
日期:2019.2.20
Potassium fluoride (KF) is an ideal reagent for fluorination because it is safe, easy to handle and low-cost. However, poor solubility in organic solvents coupled with limited strategies to control its reactivity has discouraged its use for asymmetric C-F bond formation. Here, we demonstrate that hydrogenbonding phase-transfer catalysis with KF provides access to valuable β-fluoroamines in high yields
[EN] PROCESS FOR PREPARATION OF ERIBULIN AND INTERMEDIATES THEREOF<br/>[FR] PROCÉDÉ DE PRÉPARATION D'ÉRIBULINE ET DE SES INTERMÉDIAIRES
申请人:DR REDDY'S LABORATORIES LTD
公开号:WO2017203459A1
公开(公告)日:2017-11-30
The present application relate to a process for preparation of 4-Methylene tetrahydrofuran compound of formula II, which is useful as an intermediate for the preparation of halichondrin B analogues such as Eribulin.
PROCESS FOR PREPARATION OF ERIBULIN AND INTERMEDIATES THEREOF
申请人:DR. REDDY'S LABORATORIES LIMITED
公开号:US20190276470A1
公开(公告)日:2019-09-12
The present application relate to process for preparation of tetrahydrofuran compound of formula II, 4-Methylene tetrahydrofuran compound of formula V and tetrahydropyran compound of formula IX which are useful as intermediates for the preparation of halichondrin B analogues such as Eribulin or its pharmaceutically acceptable salts.