铜(I)交换沸石Cu I -USY被证明可以在简单实用的条件下,即在室温,空气中,以甲醇为溶剂且无任何添加剂的情况下,有效地催化叠氮化钠直接芳基硼酸的叠氮化反应。这种易于制备且便宜的催化材料已被证明是可回收的,并且温和的叠氮化条件进一步显示出良好的官能团耐受性,从而导致了各种取代的(杂)芳基叠氮化物(18个例子)。有趣的是,叠氮化反应已成功地与CuAAC反应偶联,因此可以通过一锅Cu I催化过程从芳基硼酸中获得三唑。
Radical C−N Borylation of Aromatic Amines Enabled by a Pyrylium Reagent
作者:Yuanhong Ma、Yue Pang、Sonia Chabbra、Edward J. Reijerse、Alexander Schnegg、Jan Niski、Markus Leutzsch、Josep Cornella
DOI:10.1002/chem.202000412
日期:2020.3.23
Herein, we report a radical borylation of aromatic amines through a homolytic C(sp 2 )-N bond cleavage. This method capitalizes on a simple and mild activation via a pyrylium reagent ( Sc Pyry-OTf) thus priming the amino group for reactivity. The combination of terpyridine and a diboron reagent triggers a radical reaction which cleaves the C(sp 2 )-N bond and forges a new C(sp 2 )-B bond. The unique
The Multiple Facets of Iodine(III) Compounds in an Unprecedented Catalytic Auto-amination for Chiral Amine Synthesis
作者:Julien Buendia、Gwendal Grelier、Benjamin Darses、Amanda G. Jarvis、Frédéric Taran、Philippe Dauban
DOI:10.1002/anie.201602022
日期:2016.6.20
Iodine(III) reagents are used in catalytic one‐pot reactions, first as both oxidants and substrates, then as cross‐coupling partners, to afford chiral polyfunctionalized amines. The strategy relies on an initial catalytic auto C(sp3)−H amination of the iodine(III) oxidant, which delivers an amine‐derived iodine(I) product that is subsequently used in palladium‐catalyzed cross‐couplings to afford a
A General Method for Interconversion of Boronic Acid Protecting Groups: Trifluoroborates as Common Intermediates
作者:Quentin I. Churches、Joel F. Hooper、Craig A. Hutton
DOI:10.1021/acs.joc.5b00182
日期:2015.6.5
interconversion of diverse protected boronic acids, via intermediate organotrifluoroborates. N-Methyliminodiacetyl boronates, which have been hitherto resistant to direct conversion to trifluoroborates, have been shown to undergo fluorolysis at elevated temperatures. Subsequent solvolysis of organotrifluoroborates in the presence of trimethylsilyl chloride and a wide range of bis-nucleophiles enables
Palladium-Catalyzed, Direct Boronic Acid Synthesis from Aryl Chlorides: A Simplified Route to Diverse Boronate Ester Derivatives
作者:Gary A. Molander、Sarah L. J. Trice、Spencer D. Dreher
DOI:10.1021/ja1089759
日期:2010.12.22
new boron reagents and identifying robust catalytic systems for the cross-coupling of these reagents, the fundamental preparations of the nucleophilic partners (i.e., boronicacids and derivatives) has been studied to a lesser extent. Most current methods to accessboronicacids are indirect and require harsh conditions or expensive reagents. A simple and efficient palladium-catalyzed, direct synthesis
Preparation of Building Blocks for Iterative Suzuki-Miyaura Reactions via Direct Bromination of Aryl Boronic Acids: One-Pot Total Syntheses of Dictyoterphenyls A and B
作者:Chun-Young Lee、Cheol-Hong Cheon
DOI:10.1002/adsc.201700733
日期:2017.11.10
A highly efficient method for the preparation of 4-alkoxy-3-bromophenyl boronic acid N-methyliminodiacetic acid (MIDA) esters as building blocks in iterative Suzuki-Miyaura reactions from the 4-alkoxyphenylboronic acids is described using a boronic acid moiety as a blocking group in brominationreactions. With these MIDA boronates, the total syntheses of dictyoterphenyls A and B were developed in only