Synthesis of Quaternary Carbon Stereogenic Centers by Diastereoselective Conjugate Addition of Boron-Stabilized Allylic Nucleophiles to Enones
作者:Michael Z. Liang、Simon J. Meek
DOI:10.1021/jacs.0c03900
日期:2020.6.3
A method for the site- and diastereoselectiveconjugateaddition of boron-stabilized allylic nucleophiles to α,β-unsaturated ketones is disclosed. Transformations involve easily prepared γ,γ-disubstituted allyldiboron reagents, and proceed in the presence of a fluoride activator at 80 °C. Reactions proceed with a wide variety of enones and allyldiboron reagents efficiently to deliver ketone products
公开了一种将硼稳定的烯丙基亲核试剂位点和非对映选择性共轭加成到 α,β-不饱和酮的方法。转化涉及易于制备的 γ,γ-二取代烯丙基二硼试剂,并在 80 °C 下在氟化物活化剂存在下进行。反应与各种烯酮和烯丙基二硼试剂一起有效地进行,以提供含有其他难以接近的邻位 β-叔和 γ-季碳立体中心以及烯基硼部分的酮产品。该方法的实用性通过多种转化得到强调,包括交叉偶联和碳环化。
Ketone Synthesis from Benzyldiboronates and Esters: Leveraging α-Boryl Carbanions for Carbon–Carbon Bond Formation
作者:Boran Lee、Paul J. Chirik
DOI:10.1021/jacs.9b11944
日期:2020.2.5
method for the synthesis of ketones from readily available esters and benzyldiboronates is described. The synthetic method is compatible with a host of sterically differentiated alkyl groups, alkenes, acidic protons, amides and aryl rings having common organic functional groups. With esters bearing α-stereocenters, high enantiomeric excess was maintained during ketoneformation, establishing minimal competing
Formal Carbon Insertion of <i>N-</i>Tosylhydrazone into B–B and B–Si Bonds: <i>gem</i>-Diborylation and <i>gem</i>-Silylborylation of sp<sup>3</sup> Carbon
作者:Huan Li、Xianghang Shangguan、Zhikun Zhang、Shan Huang、Yan Zhang、Jianbo Wang
DOI:10.1021/ol403338s
日期:2014.1.17
A convenient method is developed to synthesize 1,1-diboronates from the corresponding N-tosylhydrazones. This method is also applicable to synthesize 1-silyl-1-boron compounds. Meanwhile, derivatization and consecutive Pd-catalyzed cross-coupling reactions with 1,1-boronates were explored, demonstrating the synthetic potential of 1,1-diboronates.