过渡金属催化的炔丙基亲电子试剂和格氏试剂的交叉偶联提供了高度官能化的产物,是极其有用的合成中间体。然而,由于具有挑战性的区域选择性,将炔丙基衍生物转化为炔丙基化合物的例子仍然有限。我们使用LaCl 3 ·2LiCl在没有配体的情况下催化格氏试剂的炔丙基化,具有高区域选择性和立体特异性。该方法显示了使用烷基或(杂)芳基格氏试剂和具有不同离去基团的炔基亲电子试剂的广泛底物范围。我们的方案进一步应用于叶毛多辛 B 的正式合成。利用天然丰富且相对无毒的镧催化剂的方法值得探索。
2-dien-1-yl)arenes exhibit novel and orthogonal reactivity under Pd catalysis in the presence of secondary amines to form enamines (concerted Pd insertion, intramolecular carbopalladation, and terminative Buchwald–Hartwig coupling) and of amides to form indoles (addition, Buchwald–Hartwig cyclization, and loss of the acetyl group). The substrates for these reactions can be accessed in a reliable and highly
Recyclable Copper(I)-Catalyzed Cross-Coupling of Trialkylsilylethynes and <i>N</i>-Tosylhydrazones Leading to the Formation of C(sp)–C(sp<sup>3</sup>) Bonds
作者:Qian Ye、Wencheng Huang、Li Wei、Mingzhong Cai
DOI:10.1021/acs.joc.2c02691
日期:2023.3.3
A highly efficient heterogeneous copper(I)-catalyzed cross-coupling of trialkylsilylethynes with N-tosylhydrazones has been achieved in dioxane at 90–110 °C via the Cu carbenemigratoryinsertion with an SBA-15-immobilized l-proline-Cu(I) complex [SBA-15-l-Proline-CuI] as the catalyst and LiOtBu as the base, leading to the formation of C(sp)–C(sp3) bonds. The reaction generates a wide variety of a
通过 Cu 卡宾迁移插入和 SBA-15-固定的l-脯氨酸-Cu (I ) 络合物 [SBA-15- l -Proline-CuI] 作为催化剂和 LiO t Bu 作为碱,导致 C(sp)–C(sp 3 ) 键的形成。该反应以中高产率生成多种烷基三烷基甲硅烷基炔烃。这种新型多相铜 (I) 配合物具有与均相 CuI 相当的催化效率,并且可以通过简单的离心过程轻松回收,并且可回收多达 12 次而不会显着损失活性。
Benzylic halides coupled with 1-alkynylmagnesium halides in the presence of a catalytic amount of Co(acaC)(3) to provide 1-aryl-2-alkynes in moderate to good yield. (c) 2006 Elsevier Ltd. All rights reserved.
Synthetic approach to aklavinone using 2-oxo-2H-pyran-5-carboxylate (coumalate) intermediates
作者:Michael E. Jung、Jeffrey A. Hagenah
DOI:10.1021/jo00386a002
日期:1987.5
Lanthanum-Catalyzed Stereospecific Cross-Coupling of Propargylic Substrates with Grignard Reagents
Transition-metal-catalyzed cross-coupling of propargylic electrophiles and Grignardreagents provides densely functionalized products that are extremely useful synthetic intermediates. However, examples of conversion of propargylic derivatives to form propargyl compounds remain limited due to the challenging regioselectivity. We use LaCl3·2LiCl to catalyze propargylation of Grignardreagents in the absence of
过渡金属催化的炔丙基亲电子试剂和格氏试剂的交叉偶联提供了高度官能化的产物,是极其有用的合成中间体。然而,由于具有挑战性的区域选择性,将炔丙基衍生物转化为炔丙基化合物的例子仍然有限。我们使用LaCl 3 ·2LiCl在没有配体的情况下催化格氏试剂的炔丙基化,具有高区域选择性和立体特异性。该方法显示了使用烷基或(杂)芳基格氏试剂和具有不同离去基团的炔基亲电子试剂的广泛底物范围。我们的方案进一步应用于叶毛多辛 B 的正式合成。利用天然丰富且相对无毒的镧催化剂的方法值得探索。