A General C(sp3)–C(sp3) Cross-Coupling of Benzyl Sulfonylhydrazones with Alkyl Boronic Acids
摘要:
A general transition-metal-free cross-coupling between benzylic sulfonylhydrazones and 1 degrees, 2 degrees, or 3 degrees alkyl boronic acids is reported. The base-promoted reaction is operationally simple and exhibits a broad substrate scope to forge a variety of alkyl-alkyl bonds, including between sterically encumbered secondary and tertiary sp(3)-carbons. The ability of this method to simplify retrosynthetic analysis is exemplified by the improved synthesis of multiple medicinally relevant scaffolds.
Decarboxylative Borylation of Stabilized and Activated Carbon Radicals
作者:Qiang Zhang、Xiaojuan Li、Weigang Zhang、Shengyang Ni、Yi Wang、Yi Pan
DOI:10.1002/anie.202008138
日期:2020.12
aliphatic and aromatic boronic esters by mild photoinduced decarboxylativeborylation. Both aryl and alkyl radicals could be generated from the leaving group‐assisted N‐hydroxybenzimidoyl chloride esters, even α‐CF3 substituted substrates could be activated for further elaboration.
Continuous Flow-Enabled Synthesis of Bench-Stable Bicyclo[1.1.1]pentane Trifluoroborate Salts and Their Utilization in Metallaphotoredox Cross-Couplings
作者:Michael D. VanHeyst、Ji Qi、Anthony J. Roecker、Jonathan M. E. Hughes、Lili Cheng、Zheyu Zhao、Jingjun Yin
DOI:10.1021/acs.orglett.0c00242
日期:2020.2.21
C(sp2)-C(sp3) cross-coupling of these fragments to afford biaryl isosteres have been scarce. Herein we describe the development of continuous flow-enabled synthesis of bench-stable bicyclo[1.1.1]pentane trifluoroborate salts. Furthermore, we demonstrate the use of metallaphotoredox conditions to enable cross-coupling of these building blocks with complex arylhalide substrates.
Exploiting the sp2 character of bicyclo[1.1.1]pentyl radicals in the transition-metal-free multi-component difunctionalization of [1.1.1]propellane
作者:Weizhe Dong、Expédite Yen-Pon、Longbo Li、Ayan Bhattacharjee、Anais Jolit、Gary A. Molander
DOI:10.1038/s41557-022-00979-0
日期:2022.9
successful use of bicyclo[1.1.1]pentane (BCP) as a para-disubstituted benzene replacement has made it a highly valuable pharmacophore. However, various challenges, including limited and lengthy access to useful BCP building blocks, are hampering early discovery research. Here we report a single-step transition-metal-free multi-component approach to synthetically versatile BCP boronates. Radicals derived from