Synthesis of Adjacent Quaternary Stereocenters by Catalytic Asymmetric Allylboration
作者:Rauful Alam、Tobias Vollgraff、Lars Eriksson、Kálmán J. Szabó
DOI:10.1021/jacs.5b07498
日期:2015.9.9
Allylboration of ketones with γ-disubstituted allylboronicacids is performed in the presence of chiral BINOL derivatives. The reaction is suitable for single-step creation of adjacent quaternary stereocenters with high selectivity. We show that, with an appropriate choice of the chiral catalyst and the stereoisomeric prenyl substrate, full control of the stereo- and enantioselectivity is possible
酮与 γ-二取代的烯丙基硼酸的烯丙基硼化是在手性 BINOL 衍生物的存在下进行的。该反应适用于单步生成相邻四元立体中心的高选择性。We show that, with an appropriate choice of the chiral catalyst and the stereoisomeric prenyl substrate, full control of the stereo- and enantioselectivity is possible in the reaction.
A Brønsted Acid Catalyzed Cascade Reaction for the Conversion of Indoles to α‐(3‐Indolyl) Ketones by Using 2‐Benzyloxy Aldehydes
作者:Ankush Banerjee、Modhu Sudan Maji
DOI:10.1002/chem.201902268
日期:2019.9.2
A Brønstedacid catalyzed, operationally simple, scalable route to several functionalized α-(3-indolyl) ketones has been developed and the long-standing regioisomeric issue has been eliminated by choosing appropriate carbonyls. A readily available and cheap bottle reagent was used as the catalyst. This protocol was also applicable to the synthesis of densely functionalized α-(3-pyrrolyl) ketones. A
Chiral Amino Alcohol Accelerated and Stereocontrolled Allylboration of Iminoisatins: Highly Efficient Construction of Adjacent Quaternary Stereogenic Centers
We have developed a highly efficient asymmetric allylboration of ketimines with nonchiral γ,γ‐disubstituted allylboronic acids by using a chiral amino alcohol as the directing group, which is otherwise challenging. The amino alcohol not only serves as a cheap source of nitrogen and chirality, but also dramatically enhances the reactivity. The versatility of this method was demonstrated by its ability
Setup of 4‐Prenylated Quinolines through Suzuki‐Miyaura Coupling for the Synthesis of Aurachins A and B
作者:Laura Stief、Andreas Speicher
DOI:10.1002/adsc.202100884
日期:2022.1.4
polyprenyl side chain could be introduced into the heterocyclic quinoline moiety through Suzuki-Miyaura coupling of the corresponding quinoline-N-oxide with a polyprenyl boronic acid. This tool could be utilized for the synthesis of the natural product Aurachin Bfrom the myxobacterium Stigmatella aurantiaca. This prenylated quinoline could then be transformed into the related Aurachin A through an
Catalytic Asymmetric Allylboration of Indoles and Dihydroisoquinolines with Allylboronic Acids: Stereodivergent Synthesis of up to Three Contiguous Stereocenters
作者:Rauful Alam、Colin Diner、Sybrand Jonker、Lars Eriksson、Kálmán J. Szabó
DOI:10.1002/anie.201608605
日期:2016.11.7
The catalyticasymmetric allylboration of cyclic imines with γ,γ‐disubstituted allylboronic acids provides products with adjacent stereocenters in high yield and stereoselectivity. Various electrophiles, including 3,4‐dihydroisoquinolines and indoles, were prenylated in a fully stereodivergent fashion by switching the E/Z geometry of the allylboronate and/or the enantiomer of the BINOL catalyst. 3‐Methylindole