Enantioselective Iridium-Catalyzed Allylic Substitution with 2-Methylpyridines
作者:Xi-Jia Liu、Shu-Li You
DOI:10.1002/anie.201700433
日期:2017.3.27
An enantioselective iridium‐catalyzed allylicsubstitution with a set of highly unstabilized nucleophiles generated in situ from 2‐methylpyridines is described. Enantioenriched 2‐substituted pyridines, which are frequently encountered in natural products and pharmaceuticals, could be easily constructed by this simple method in good yields and excellent enantioselectivity. The synthetic utility of the
描述了用2-甲基吡啶原位生成的一组高度不稳定的亲核试剂进行对映选择性铱催化的烯丙基取代。天然产物和药物中经常遇到的富含对映体的2-取代的吡啶可以通过这种简单方法以高收率和出色的对映选择性轻松地构建。吡啶产物的合成用途通过已报道的Na + / H +交换抑制剂的关键中间体的合成和(-)-番茄红素A的总合成得以证明。
Photocatalytic Synthesis of Substituted Cyclic Carbonate Monomers for Ring‐Opening Polymerization
作者:Cristina Maquilón、Francesco Della Monica、Bart Limburg、Arjan W. Kleij
DOI:10.1002/adsc.202100654
日期:2021.8.13
photocatalytic protocol has been developed for the conversion of γ-mono- and γ,γ-disubstituted allyl carbonates in the presence of Umemoto's reagent to afford substituted six-membered cyclic carbonates. Variation and diversification of the carbonate ring substitution provides access to new monomers useful in ring-opening polymerization leading to polycarbonates with potentially tailored properties, as illustrated
已经开发了一种操作温和的基于钌的光催化方案,用于在 Umemoto 试剂存在下转化 γ-单和 γ,γ-二取代的烯丙基碳酸酯,以提供取代的六元环状碳酸酯。碳酸酯环取代的变化和多样化提供了获得可用于开环聚合的新单体的途径,导致聚碳酸酯具有潜在的定制特性,如使用具有不同 pi 堆积能力的单体的比较实验所示。
A highly efficient catalyst for Pd-catalyzed cyclopropanation was developed using a bulkier N-heterocyclic carbene ligand, with which the nitriles reacted with mono substitutedallyl reagents to afford cyclopropanes in high yields with high cyclopropanation/allylation and enantioselectivities. The reasons for cyclopropanation were investigated and the usefulness of the products was demonstrated.