Development of the Suzuki−Miyaura Cross-Coupling Reaction: Use of Air-Stable Potassium Alkynyltrifluoroborates in Aryl Alkynylations
作者:Gary A. Molander、Bryson W. Katona、Fouzia Machrouhi
DOI:10.1021/jo0262356
日期:2002.11.1
cross-coupling reaction of potassiumalkynyltrifluoroborates with aryl halides or triflates proceeds readily with moderate to excellent yields. The potassiumalkynyltrifluoroborates are air- and moisture-stable crystalline solids that can be stored indefinitely, which will provide an advantage in applications to combinatorial chemistry. The alkynyl cross-coupling reaction can be effected using 9 mol % of PdCl2(dppf)
Photoinduced 1,2-dicarbofunctionalization of alkenes with organotrifluoroborate nucleophiles <i>via</i> radical/polar crossover
作者:María Jesús Cabrera-Afonso、Anasheh Sookezian、Shorouk O. Badir、Mirna El Khatib、Gary A. Molander
DOI:10.1039/d1sc02547c
日期:——
postulated to proceed throughphotochemicalradical/polar crossover to afford a key carbocation species that undergoes subsequent trapping with organoboron nucleophiles to accomplish the carboallylation, carboalkenylation, carboalkynylation, and carboarylation of alkenes with regio- and chemoselective control. The mechanistic intricacies of this difunctionalization were elucidated through Stern–Volmer quenching
Practical Metal-Free C(sp<sup>3</sup>)H Functionalization: Construction of Structurally Diverse α-Substituted<i>N</i>-Benzyl and<i>N</i>-Allyl Carbamates
is a practical and universal CH functionalization of readily removable N‐benzyl and N‐allyl carbamates, with a wide range of nucleophiles at ambient temperature promoted by Ph3CClO4. The metal‐free reaction has an excellent functional‐group tolerance, and displays a broad scope with respect to both N‐carbamates and nucleophile partners (a variety of organoboranes and CH compounds). The synthetic utility
Structurally Diverse α-Substituted Benzopyran Synthesis through a Practical Metal-Free C(sp<sup>3</sup>)–H Functionalization
作者:Wenfang Chen、Zhiyu Xie、Hongbo Zheng、Hongxiang Lou、Lei Liu
DOI:10.1021/ol503004a
日期:2014.11.21
A trityl ion-mediated practical C–H functionalization of a variety of benzopyrans with a wide range of nucleophiles (organoboranes and C–H molecules) at ambient temperature has been disclosed. The metal-free reaction has an excellent functional group tolerance and high chemoselectivity and displays a broad scope with respect to both benzopyran and nucleophile partners, efficiently affording a collection
Heterocycle Synthesis Based on Allylic Alcohol Transposition Using Traceless Trapping Groups
作者:Youwei Xie、Paul E. Floreancig
DOI:10.1002/anie.201402010
日期:2014.5.5
Allylic alcohols undergo transposition reactions in the presence of Re2O7 whereby the equilibrium can be dictated by trapping one isomer with a pendent electrophile. Additional ionization can occur when the trapping group is an aldehyde or ketone, thus leading to cyclic oxocarbenium ion formation. Terminating the process through bimolecular nucleophilic addition into the intermediate provides a versatile
烯丙醇在Re 2 O 7的存在下进行转座反应,从而可以通过用一种亲电亲和剂捕获一种异构体来控制平衡。当捕获基团是醛或酮时,可能会发生其他电离,从而导致形成环氧碳鎓离子。通过将双分子亲核加成至中间物来终止该过程,为合成各种含氧杂环化合物提供了一种通用的方法。了解序列中各步骤的相对速率会导致设计反应,从而创建多个具有良好至极佳控制水平的立体中心。