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
Highly enantioselective reduction of ketones by chiral diol-modified lithium aluminum hydride reagents
作者:Yunlai Ren、Xinzhe Tian、Kunpeng Sun、Jian Xu、Xianlun Xu、Shijie Lu
DOI:10.1016/j.tetlet.2005.11.062
日期:2006.1
Some readily available chiral diols from indene and d-mannitol were investigated as chiral modifiers in lithiumaluminumhydridereduction of ketones, and it was discovered that further modification of these reducing reagents by a simple a-amino alcohol resulted in a remarkable increase in optical yield. Among the investigated chiral modifiers, chiral diol 1 gave the highest enantioselectivities.
Asymmetric Hydrophosphination of Heterobicyclic Alkenes: Facile Access to Phosphine Ligands for Asymmetric Catalysis
作者:Zhiwu Lu、Haoyang Zhang、Zhiping Yang、Ning Ding、Ling Meng、Jun Wang
DOI:10.1021/acscatal.8b04787
日期:2019.2.1
Asymmetric hydrophosphination is the most atomically economical and straightforward approach to the construction of chiral organophosphorus compounds. Good stereoselectivities have been achieved in asymmetric hydrophosphination of an electron-deficient C═C double bond, but substrates involving nonpolar C═C bonds remain difficult and are rarely tackled. Herein, we report asymmetric hydrophosphination
Enantioselective addition of organozinc reagents to carbonyl compounds catalyzed by a camphor derived chiral γ-amino thiol ligand
作者:Hsyueh-Liang Wu、Ping-Yu Wu、Ying-Ni Cheng、Biing-Jiun Uang
DOI:10.1016/j.tet.2015.07.038
日期:2016.5
synthesis of the chiral camphor derived γ-amino thiol ligand 17 and its application in catalytic enantioselective carbon-carbon forming reactions through the addition of organozinc reagents to carbonyl compounds is described. The catalytic activity and enantioselectivity of ligand 17 is demonstrated in the enantioselective addition of various organozinc reagents to aldehydes and ketoesters, offering the corresponding