Highly Stereoselective Synthesis of Tetrasubstituted Acyclic All-Carbon Olefins via Enol Tosylation and Suzuki–Miyaura Coupling
作者:Beryl X. Li、Diane N. Le、Kyle A. Mack、Andrew McClory、Ngiap-Kie Lim、Theresa Cravillion、Scott Savage、Chong Han、David B. Collum、Haiming Zhang、Francis Gosselin
DOI:10.1021/jacs.7b05071
日期:2017.8.9
A highly stereocontrolled synthesis of tetrasubstituted acyclic all-carbon olefins has been developed via a stereoselective enolization and tosylate formation, followed by a palladium-catalyzed Suzuki-Miyaura cross-coupling of the tosylates and pinacol boronic esters in the presence of a Pd(OAc)2/RuPhos catalytic system. Both the enol tosylation and Suzuki-Miyaura coupling reactions tolerate an array
Synthesis of Highly Stereodefined Tetrasubstituted Acyclic All-Carbon Olefins via a <i>Syn</i>-Elimination Approach
作者:Ngiap-Kie Lim、Patrick Weiss、Beryl X. Li、Christina H. McCulley、Stephanie R. Hare、Bronwyn L. Bensema、Teresa A. Palazzo、Dean J. Tantillo、Haiming Zhang、Francis Gosselin
DOI:10.1021/acs.orglett.7b03141
日期:2017.11.17
An efficient synthesis of stereodefined tetrasubstituted acyclic all-carbon olefins has been developed via a bis(2,6-xylyl)phosphate formation of stereoenriched tertiary alcohols, followed by in situ syn-elimination of the corresponding phosphates under mild conditions. This chemistry tolerates a wide variety of electronically and sterically diverse substrates and generates the desired tetrasubstituted
Synthesis of Bis(heteroaryl) Ketones by Removal of Benzylic CHR and CO Groups
作者:Arun Maji、Sujoy Rana、Akanksha、Debabrata Maiti
DOI:10.1002/anie.201308785
日期:2014.2.24
A copper‐catalyzed method for synthesis of diaryl ketones (Ar‐CO‐Ar′) through removal of benzylic ‐CH2‐, ‐CO‐, and ‐CHR‐ groups from Ar‐CO‐CXR‐Ar′ has been discovered. A number of symmetrical and unsymmetrical heterocyclic ketones, which are usually difficult to synthesize, can be prepared in good to excellent yields. This method was applied to the synthesis of the nonsteroidal anti‐inflammatory drug
发现了一种铜催化的方法,该方法通过从Ar-CO-CXR-Ar'中去除苄基-CH 2 -,-CO-和-CHR-基团来合成二芳基酮(Ar-CO-Ar')。可以以高至优异的产率制备通常难以合成的许多对称和不对称的杂环酮。该方法适用于非甾体类抗炎药Suprofen的合成(三步收率47%)。基于初步的力学和动力学研究,提出了一种活性Cu / O 2物种来介导重排反应。
A highly active and selective palladium pincer catalyst for the formation of α-aryl ketones via cross-coupling
作者:Alejandro Bugarin、Brian T. Connell
DOI:10.1039/c1cc12071a
日期:——
Several air and moisture stable Pd(II) pincer complexes were synthesized via oxidative addition of Pd(0) to novel PheBox pincer ligand precursors. Low loadings (1 mol%) of the Pd complex [t-BuPhebox-Me2]PdBr are capable of efficiently promoting the selective α-monoarylation of a variety of ketones with numerous aryl bromides in only 1 h at 70 °C with 82â99% yields.
Stereoconvergent and -divergent Synthesis of Tetrasubstituted Alkenes by Nickel-Catalyzed Cross-Couplings
作者:Daniel Zell、Cian Kingston、Janis Jermaks、Sleight R. Smith、Natalie Seeger、Jana Wassmer、Lauren E. Sirois、Chong Han、Haiming Zhang、Matthew S. Sigman、Francis Gosselin
DOI:10.1021/jacs.1c08399
日期:2021.11.17
of enol tosylates and boronic acid esters. Either diastereomeric product was selectively accessed from a mixture of enol tosylate starting material diastereomers in a convergent reaction by judicious choice of the ligand and reaction conditions. A similar protocol also enabled a divergent synthesis of each product isomer fromdiastereomericallypure enol tosylates. Notably, high-throughput optimization
我们报告了一种通过镍催化的 Suzuki-Miyaura烯醇甲苯磺酸酯和硼酸酯的交叉偶联非对映选择性获得四取代烯烃的方法的发展。通过明智地选择配体和反应条件,在收敛反应中从烯醇甲苯磺酸酯起始材料非对映异构体的混合物中选择性地获得任一非对映异构体产物。类似的协议还能够从非对映纯烯醇甲苯磺酸盐中不同地合成每种产品异构体。值得注意的是,单膦配体的高通量优化是由海妖的化学空间分析指导的库以确保检查多种配体选择。结果的立体电子分析提供了对这种转变中反应性和选择性配体的要求的深入了解。然后在各种四取代烯烃的立体选择性合成中探索了优化催化体系的合成效用,产率高达 94%,非对映体比高达 99:1 Z / E和 93: 7 E / Z。此外,详细的计算分析和实验机制研究为影响交叉偶联选择性的潜在异构化过程的性质提供了重要见解。