Enantiospecific Synthesis of
<i>ortho</i>
‐Substituted 1,1‐Diarylalkanes by a 1,2‐Metalate Rearrangement/
<i>anti</i>
‐S
<sub>
<i>N</i>
</sub>
2′ Elimination/Rearomatizing Allylic Suzuki–Miyaura Reaction Sequence
作者:Belén Rubial、Beatrice S. L. Collins、Raphael Bigler、Stefan Aichhorn、Adam Noble、Varinder K. Aggarwal
DOI:10.1002/anie.201811343
日期:2019.1.28
The one‐pot sequential coupling of benzylamines, boronic esters, and aryl iodides has been investigated. In the presence of an N‐activator, the boronate complex formed from an ortho‐lithiated benzylamine and a boronic ester undergoes stereospecific 1,2‐metalate rearrangement/anti‐SN2′ elimination to form a dearomatized tertiary boronic ester. Treatment with an aryl iodide under palladium catalysis
研究了苄胺、硼酸酯和芳基碘化物的一锅顺序偶联。在 N-活化剂存在下,由邻位锂化苄胺和硼酸酯形成的硼酸酯络合物经历立体定向 1,2-金属化物重排/抗 S N 2' 消除,形成脱芳构化叔硼酸酯。在钯催化下用芳基碘化物处理导致 γ-选择性烯丙基 Suzuki-Miyaura 交叉偶联重新芳构化,生成 1,1-二芳基烷烃。当使用对映体富集的 α-取代苄胺时,会形成具有高立体特异性的相应 1,1-二芳基烷烃。
Synthesis of Biaryl Ethers by the Copper-Catalyzed Chan–Evans–Lam Etherification from Benzylic Amine Boronate Esters
作者:Justin S. Marcum、Kathryn A. McGarry、Carl J. Ferber、Timothy B. Clark
DOI:10.1021/acs.joc.6b01254
日期:2016.9.2
benzylic amines with phenols has been achieved to provide biaryl ethers that are prevalent in biologically active compounds. A variety of substitution patterns on the aryl boronate ester and the phenol are tolerated under the reaction conditions, providing moderate to high yields. A competition reaction between phenol and aniline revealed condition-dependent selectivity in which the phenol could be highly
Enantiospecific Synthesis of <i>ortho</i>-Substituted Benzylic Boronic Esters by a 1,2-Metalate Rearrangement/1,3-Borotropic Shift Sequence
作者:Stefan Aichhorn、Raphael Bigler、Eddie L. Myers、Varinder K. Aggarwal
DOI:10.1021/jacs.7b05880
日期:2017.7.19
ortho-substituted benzylic boronic esters with formal 1,1′-benzylidene insertion into the C–B bond. The reaction occurs by a SN2′ elimination and 1,2-metalate rearrangement of the N-activated boronate complex to afford a dearomatized intermediate, which undergoes a Lewis-acid catalyzed 1,3-borotropic shift to afford the boronic ester products in high yield and with excellent enantiospecificity. The use of
已经研究了苄胺和硼酸酯之间的偶联反应。邻-Lithiated苄胺与硼酸酯反应,并且一个Ñ -activator,得到邻位与正规1,1'-亚苄基取代的插入苄硼酸酯到C-B键。该反应通过S N 2'的消除和N活化的硼酸酯络合物的1,2-金属化物重排而得到脱芳香化的中间体,该中间体经过路易斯酸催化的1,3-硼向转变以得到硼酸酯产物。高收率和优异的对映体特异性。使用富含对映体的α-取代的苄胺得到相应的具有高ee的仲硼酸酯。