New C2-symmetric tetrafluorobenzobarreleneligands were prepared and applied successfully to the rhodium-catalyzedasymmetric addition of arylboronic acids to aromatic aldehydes giving chiral diarylmethanols in high yield with high enantioselectivity.
Synthesis of the bifunctional BINOL ligands and their applications in the asymmetric additions to carbonyl compounds
作者:Ying-Chuan Qin、Lan Liu、Michal Sabat、Lin Pu
DOI:10.1016/j.tet.2006.06.049
日期:2006.10
the diphenylzinc addition which often require the addition of a significant amount of diethylzinc with cooling (or heating) the reaction mixture in order to achieve high enantioselectivity, using (S)-8 needs no additive and gives excellent results at room temperature. (S)-8 in combination with diethylzinc and Ti(OiPr)4 can catalyze the highly enantioselective phenylacetylene addition to aromatic aldehydes
分别从BINOL和H 8 BINOL与吗啉代甲醇的反应中开发了双功能BINOL和H 8 BINOL配体(S)-6和(S)-8的高效一步合成方法。这些化合物的X射线分析表明它们在结构上有相似之处和不同之处。双功能H 8 BINOL(S)-8已发现对二苯基锌与许多脂族和芳族醛的反应具有很高的对映选择性,尤其是对于线性脂族醛而言,对映选择性最强的催化剂。与开发用于添加二苯锌的其他催化剂不同,该催化剂通常需要在冷却(或加热)的同时添加大量的二乙基锌以实现高对映选择性,使用(S)-8无需添加剂,在室温下可获得优异的结果温度。(S)-8与二乙基锌和Ti(O i Pr)4结合可以催化高度对映选择性的苯乙炔加成芳族醛。尽管对映选择性还不是很高,但它在室温下还可以促进苯乙炔向苯乙酮的添加。在不使用Ti(O i Pr)4和路易斯碱添加剂的情况下,(S)-8与二乙基锌结合可以催化丙酸甲酯与醛的反应,形成高官能度
Asymmetric Transfer Hydrogenation of <i>o</i>-Hydroxyphenyl Ketones: Utilizing Directing Effects That Optimize the Asymmetric Synthesis of Challenging Alcohols
作者:Ye Zheng、Guy J. Clarkson、Martin Wills
DOI:10.1021/acs.orglett.0c01213
日期:2020.5.1
A systematic range of o-hydroxyphenyl ketones were reduced under asymmetrictransferhydrogenation conditions using the C3-tethered catalyst 2. Two directing effects, i.e., an o-hydroxyphenyl coupled to a bulky aromatic on the opposite side of the ketone substrate, combine in a matched manner to deliver reduction products with very high enantiomeric excess.
Catalytic enantioselective arylation of aldehydes: boronic acids as a suitable source of transferable aryl groups
作者:Antonio L. Braga、Diogo S. Lüdtke、Fabrício Vargas、Marcio W. Paixão
DOI:10.1039/b501485a
日期:——
The catalytic enantioselective arylation of several aldehydes using boronic acids as the source of transferable aryl groups is described; the reaction is found to proceed in excellent yields and high enantioselectivities (up to 97% ee) in the presence of a chiral amino alcohol.
Highly Enantioselective Addition of In Situ Prepared Arylzinc to Aldehydes Catalyzed by a Series of Atropisomeric Binaphthyl-Derived Amino Alcohols
作者:Gui Lu、Fuk Yee Kwong、Ji-Wu Ruan、Yue-Ming Li、Albert S. C. Chan
DOI:10.1002/chem.200501048
日期:2006.5.15
catalyst, both enantiomers of many pharmaceutically interesting diarylmethanols can be obtained by the proper combination of various arylzinc reagents with different aldehydes; this catalytic system also works well for the phenylation of aliphatic aldehydes to give up to 96 % ee.