A benzene-bridged divanadium complex-early transition metal catalyst for alkene alkylarylation with PhI(O<sub>2</sub>CR)<sub>2</sub><i>via</i> decarboxylation
作者:Lei Zhang、Hongfei Zhou、Shaokun Bai、Shaodan Li
DOI:10.1039/d0dt04295a
日期:——
alkene alkylarylation with hypervalent iodine(III) reagents (HIRs) via decarboxylation to generate regioselectively diverse indolinones. Furthermore, the mild nature of this reaction was amenable to a wide range of functionalities on alkenes and HIRs. Mechanistic studies revealed a relay sequence of decarboxylative radical alkylation/radical arylation/oxidative re-aromatization.
全面研究了苯桥二钒配合物的合成,结构和催化活性。通过以苯为溶剂用石墨烯酸钾(KC 8)还原由β-二酮化支持的(Nacnac)VCl 2(1)(Nacnac =(2,6- i Pr 2 C 6 H 3 NCMe)2 HC)访问苯桥连的倒夹心二钒配合物(μ-η 6:η 6 -C 6 H ^ 6)[V(Nacnac)] 2(图2a),它可催化与高价碘烯烃alkylarylation(III试剂(HIR)通过脱羧生成区域选择性多样的吲哚啉酮。此外,该反应的温和性质适合于烯烃和HIR的多种官能度。机理研究揭示了脱羧自由基烷基化/自由基芳基化/氧化再芳构化的中继序列。
A Catalyst-Free Minisci-Type Reaction: the C-H Alkylation of Quinoxalinones with Sodium Alkylsulfinates and Phenyliodine(III) Dicarboxylates
A direct C–H alkylation of quinoxalinones at the C‐3 position with sodiumalkylsulfinates and phenyliodine(III) dicarboxylates has been developed under catalyst‐free conditions. A series of 3‐alkylquinoxalinones were afforded in moderate to excellent yields in this protocol, which offers a practical and efficient access to biologically interesting 3‐alkylquinoxalin‐2(1H)‐one derivatives.
Direct β-C(sp<sup>3</sup>)–H Acetoxylation of Aliphatic Carboxylic Acids
作者:Kiron K. Ghosh、Alexander Uttry、Aylin Koldemir、Mike Ong、Manuel van Gemmeren
DOI:10.1021/acs.orglett.9b02741
日期:2019.9.6
strong directinggroups. In our studies, we found that the use of a "traceless base" was crucial for the development of a synthetically useful transformation. Furthermore, the synthetic utility of the products obtained was demonstrated by their use in subsequent transformations.
Pd(II)-Catalyzed Chemoselective Acetoxylation of C(sp<sup>2</sup>)–H and C(sp<sup>3</sup>)–H Bonds in Tertiary Amides
作者:Muniyappa Vijaykumar、Benudhar Punji
DOI:10.1021/acs.joc.1c00629
日期:2021.6.18
Palladium-catalyzed chemoselective C(sp2)–H and C(sp3)–H acetoxylation of synthetically useful tertiary amides is reported under relatively mild reaction conditions. This protocol proceeds through the assistance of a weakly coordinated directing group (C═O) and requires low catalyst (1.0 mol %) loading. Diverse functionalities, such as C(sp2)–Cl, C(sp3)–Cl, −CF3, −COOEt, and −NO2 groups, including
A practical method for the preparation of (diacetoxyiodo)arene ArI(OAc)2 is described. The use of commercially available sodium hypochlorite pentahydrate (NaClO·5H2O) enabled safe, rapid, and inexpensive oxidation of iodoarenes with electron-withdrawing and -donating substituents. The method allows tandem divergent access to synthetically useful organo-λ3-iodanes such as hydroxyl(tosyloxy)iodobenzene