Carbon Atom Insertion into Pyrroles and Indoles Promoted by Chlorodiazirines
作者:Balu D. Dherange、Patrick Q. Kelly、Jordan P. Liles、Matthew S. Sigman、Mark D. Levin
DOI:10.1021/jacs.1c06287
日期:2021.8.4
calculations supporting a selectivity-determining cyclopropanation step. Computations surprisingly indicate that the stereochemistry of cyclopropanation is of little consequence to the subsequent electrocyclicringopening that forges the pyridine core, due to a compensatory homoaromatic stabilization that counterbalances orbital-controlled torquoselectivity effects. The utility of this skeletal transform is
Unified Access to Pyrimidines and Quinazolines Enabled by N–N Cleaving Carbon Atom Insertion
作者:Ethan E. Hyland、Patrick Q. Kelly、Alexander M. McKillop、Balu D. Dherange、Mark D. Levin
DOI:10.1021/jacs.2c09616
日期:2022.10.26
transformations with the capacity to modify such molecular skeletons with modularity remain highly desirable. Ring expansions that enable interconversion of privileged heterocyclic motifs are especially interesting in this regard. As such, the known mechanisms for ring expansion and contraction determine the classes of heterocycle amenable to skeletal editing. Herein, we report a reaction that selectively cleaves
Reactions of Frustrated Lewis Pairs with Chloro‐Diazirines: Cleavage of N=N Double Bonds
作者:Dipendu Mandal、Ting Chen、Zheng‐Wang Qu、Stefan Grimme、Douglas W. Stephan
DOI:10.1002/anie.202209241
日期:2022.9.12
lead to rapid loss of N2, reactions of phosphine/borane FLPs with chlorodiazirines prompt N=N double bond cleavage, affording linked phosphinimide/amidoborate zwitterions of the general form R3PNC(Ar)NR′BX(C6F5)2. A detailed DFT mechanistic study shows that these reactions proceed via FLP addition to the N=N bond.
虽然已知 FLP 与重氮甲烷的反应会导致 N 2的快速损失,但膦/硼烷 FLP 与氯二氮丙啶的反应会促进 N=N 双键断裂,从而提供通式 R 3 PNC(Ar) 的连接的膦酰亚胺/氨基硼酸盐两性离子NR′BX(C 6 F 5 ) 2 。详细的 DFT 机理研究表明,这些反应通过 FLP 加成到 N=N 键上进行。
Photochemically Mediated Ring Expansion of Indoles and Pyrroles with Chlorodiazirines: Synthetic Methodology and Thermal Hazard Assessment
作者:Ben W. Joynson、Graham R. Cumming、Liam T. Ball
DOI:10.1002/anie.202305081
日期:2023.8
demonstrate that pyridinium and quinolinium salts can be accessed by the insertion of a single C-atom from an arylchlorodiazirine into the parent N-alkyl pyrrole or indole. The azinium products of ringexpansion are activated towards oxygenation and hydrogenation, expediting further structural diversification. Safer methods for the use of diazirines as carbene precursors have been developed with insight
我们证明,吡啶盐和喹啉盐可以通过将芳基氯二嗪中的单个 C 原子插入母体 N-烷基吡咯或吲哚来获得。扩环的氮化产物被激活,进行氧化和氢化,加速了进一步的结构多样化。利用差示扫描量热法的洞察力,已经开发了使用二嗪嗪作为卡宾前体的更安全的方法。