Mechanism and scope of salen bifunctional catalysts in asymmetric aldehyde and α-ketoester alkylation
作者:Michael W. Fennie、Erin F. DiMauro、Erin M. O'Brien、Venkatachalam Annamalai、Marisa C. Kozlowski
DOI:10.1016/j.tet.2005.03.117
日期:2005.6
complexes of C2-symmetric Lewisacid/Lewis base salen ligands provide bifunctional activation resulting in rapid rates in the enantioselective addition of diethylzinc to aldehydes (up to 92% ee). Further experiments probed the reactivity of the individual Lewisacid and Lewis base components of the catalyst and established that both moieties are essential for asymmetriccatalysis. These catalysts are also
C 2对称的路易斯酸/路易斯碱塞伦配体的金属配合物提供双功能激活,从而使二乙基锌对醛的对映选择性加成速率加快(最高ee为92%)。进一步的实验探查了催化剂中各个路易斯酸和路易斯碱组分的反应性,并确定这两个部分对于不对称催化都是必不可少的。这些催化剂在将二乙基锌不对称加成到α-酮酸酯中也是有效的。这一发现意义重大,因为单独的α-酮酸酯充当其自身的配体,以加速Et 2的外消旋1,2-羰基加成反应锌与外消旋羰基还原。后者通过金属茂途径进行,并且通常占主要产物。奇异的路易斯酸催化剂不能在这两个竞争路径上加速对映选择性的1,2-加成。然而,双官能氨基塞伦催化剂以优异的收率,完全的化学选择性和良好的对映选择性(高达88%ee)快速提供对映体富集的1,2-加成产物。合成了双功能氨基塞隆的文库,并在该反应中进行了评估。已经在鸦片拮抗剂的合成中证明了α-酮酸酯方法的实用性。
Osmium(0)-Catalyzed C–C Coupling of Ethylene and α-Olefins with Diols, Ketols, or Hydroxy Esters via Transfer Hydrogenation
作者:Boyoung Y. Park、Tom Luong、Hiroki Sato、Michael J. Krische
DOI:10.1021/acs.joc.6b01923
日期:2016.9.16
regioisomers. The collective data, including deuteriumlabelingstudies, are consistent with a catalytic mechanism involving olefin–dione oxidative coupling to form an oxa-osmacyclopentane, which upon reductive cleavage via hydrogentransfer from the secondary alcohol reactant releases the product of carbinol C-alkylation with regeneration of the ketone. Single-crystal X-ray diffraction data of the
[EN] N-BENZYL-3-INDENYLACETAMIDES DERIVATIVES FOR TREATING NEOPLASIA<br/>[FR] DERIVES DE N-BENZYL-3-INDENYLACETAMIDES POUR TRAITER DES NEOPLASIES
申请人:CELL PATHWAYS, INC.
公开号:WO1999031065A1
公开(公告)日:1999-06-24
(EN) Substituted condensation products of N-benzyl-3-indenylacetamides of formula (I) with heterocyclic aldehydes are useful for inducing or promoting apoptosis and for arresting uncontrolled neoplastic cell proliferation, and are specifically useful in the arresting and treatment of neoplasias, including precancerous and cancerous lesions.(FR) L'invention concerne des produits de condensation substitués de N-benzyl-3-indénylacétamides de formule (I) avec des aldéhydes hétérocycliques, qui sont utiles pour provoquer ou activer l'apoptose et pour enrayer une prolifération incontrôlée de cellules néoplasiques, et spécifiquement utiles pour enrayer et traiter des néoplasies, y compris des lésions précancéreuses et cancéreuses.