Amphiphilic reactions by means of exceptionally bulky organoaluminum reagents. Rational approach for obtaining unusual equatorial, anti-Cram, and 1,4 selectivity in carbonyl alkylation
Rhodium-catalyzed enantioselective 1,4-additions of arylboronic acids to substituted enones
作者:Laura Mediavilla Urbaneja、Norbert Krause
DOI:10.1016/j.tetasy.2006.01.006
日期:2006.2
The rhodium-catalyzed enantioselective 1,4-addition of arylboronicacids to the bifunctional Michael acceptors 1–3 in the presence of phosphoramidites L2–L4 occurs regioselectively at the endocyclic C–C double bond and in up to 95% ee. The presence of KOH is required to increase the reactivity so that less boronic acid and lower reaction temperatures can be used. The corresponding addition to chiral
Catalytic asymmetricconjugate arylation of racemic 6-substituted cyclohexenones with arylboronic acids was catalyzed by 3 mol % of chiral amidophosphane-[RhCl(C2H4)]2 in a 10:1 mixture of 1,4-dioxane and water at 70 °C to afford a nearly 1:1 mixture of trans- and cis-5-aryl-2-substituted cyclohexanones in high enantioselectivity, which was subsequently epimerized with sodium ethoxide in ethanol to
外消旋6-取代的环己烯酮与芳基硼酸的催化不对称共轭芳基化反应是在70° C的1:4-二恶烷和水的10:1混合物中,由3 mol%的手性酰胺基膦-[RhCl(C 2 H 4)] 2催化下反应,得到几乎1:1的混合物的反式-和顺式-5-芳基-2-取代的在高对映选择性的环己酮,随后将其差向异构化以乙醇钠在乙醇中,得到热力学稳定的反式-5-芳基-2-取代的环己酮ee高达99–97%,两步收率高。
Accessing Phase-Transfer Catalysts and a Phosphoramidite Ligand <i>via</i> the Asymmetric Intramolecular Hydroamination Reaction
作者:Daven Foster、Stephen A. Moggach、Reto Dorta
DOI:10.1021/acs.organomet.3c00124
日期:2023.7.10
asymmetric hydroamination (HA) reaction to a point where essentially enantiopure products can be obtained. The question then arose as to whether we can apply the reaction in useful ways beyond the synthesis of natural/pharmaceutically relevant products. In the present paper, we incorporate a select few HA products for the production of new chiral phase-transfercatalysts. These species are synthesized
在过去的几年里,我们的团队开发了分子内不对称氢胺化(HA)反应,基本上可以得到对映体纯的产品。接下来的问题是,除了天然/药物相关产品的合成之外,我们是否可以以有用的方式应用该反应。在本文中,我们结合了一些精选的 HA 产品来生产新型手性相转移催化剂。这些物质是由新的螺环 HA 产品通过一两个合成步骤合成的,并应用于经典的取代反应,显示出可忽略不计的对映选择性。在第二个应用中,我们介绍了一种新型亚磷酰胺配体,该配体是通过将 BINOL(1,1'-双-2-萘酚)和光学纯 HA 产品与三氯化磷结合而获得的。
MARUOKA, KEIJI;ITOH, TAKAYUKI;SAKURA, MINORU;NONOSHITA, KATSUMASA;YAMAMOT+, J. AMER. CHEM. SOC., 110,(1988) N 11, 3588-3597