Nickel‐Catalyzed Amination of Silyloxyarenes through C–O Bond Activation
作者:Eric M. Wiensch、John Montgomery
DOI:10.1002/anie.201806790
日期:2018.8.20
Silyloxyarenes were utilized as electrophilic coupling partners with amines in the synthesis of aniline derivatives. A diverse range of amine substrates were used, including cyclic or acyclic secondary amines, secondary anilines, and stericallyhindered primary anilines. Additionally, a range of stericallyhindered and unhindered primary aliphatic amines were employed, which have previously been challenging with
Silyloxyarenes as Versatile Coupling Substrates Enabled by Nickel-Catalyzed C–O Bond Cleavage
作者:Eric M. Wiensch、David P. Todd、John Montgomery
DOI:10.1021/acscatal.7b02025
日期:2017.9.1
coupling processes. The C(sp2)–O bond of aryl silyl ethers is directly transformed into C–H or C–Si bonds using Ti(O-i-Pr)4 or trialkylsilanes as reagents using nickel catalysts with N-heterocyclic carbene (NHC) ligands. Paired with the useful characteristics of silyl protecting groups, these methods enable protected hydroxyls to directly participate in high-value bond-forming steps rather than requiring
甲硅烷氧基芳烃在各种镍催化的偶联过程中被证明是一类通用的底物。使用Ti(O- i -Pr)4将芳基甲硅烷基醚的C(sp 2)-O键直接转变为CH-H或C-Si键或三烷基硅烷作为试剂,使用具有N-杂环卡宾(NHC)配体的镍催化剂。这些方法与甲硅烷基保护基团的有用特性相结合,使受保护的羟基直接参与高价值的键形成步骤,而不需要常规方法所需的脱保护活化策略。甲硅烷基氧芳烃的这些过程提供了与广泛使用的酚衍生物(例如新戊酸芳基酯,氨基甲酸酯和甲基醚)互补的反应性,因此能够在不保护基团和不活化基团的情况下,对复杂的底物进行化学选择性衍生化提供强大的策略。
Cross-Coupling Reactions of Aromatic and Heteroaromatic Silanolates with Aromatic and Heteroaromatic Halides
作者:Scott E. Denmark、Russell C. Smith、Wen-Tau T. Chang、Joseck M. Muhuhi
DOI:10.1021/ja8091449
日期:2009.3.4
use of bis(tri-tert-butylphosphine)palladium. Under the optimized conditions, electron-rich, electron-poor, and stericallyhindered arylsilanolates afford cross-coupling products in good yields. Many functional groups are compatible with the coupling conditions such as esters, ketones, acetals, ethers, silyl ethers, and dimethylamino groups. Two particularly challenging substrates, (2-benzofuranyl)dimethylsilanolate
Br/Mg-exchange reaction using reagents of the general formula R2Mg (R = sBu, Mes). Highly sensitive functional groups, such as triazene or nitro, are tolerated in these exchange reactions, enabling the synthesis of various functionalized (hetero)arene and alkene derivatives after quenching with several electrophiles including allyl bromides, acylchlorides, aldehydes, ketones, and aryl iodides.
在 –78 °C 和 25 °C 之间,通过 I/Mg 或 Br/Mg 交换反应,在甲苯中,在 10 到 120 分钟内,使用以下试剂制备各种多官能化二(杂)芳基和二烯基镁试剂通式 R2Mg (R = sBu, Mes)。在这些交换反应中可以耐受三氮烯或硝基等高度敏感的官能团,在用烯丙基溴、酰氯、醛、酮和芳基碘等多种亲电试剂淬灭后,可以合成各种功能化的(杂)芳烃和烯烃衍生物.
Suzuki–Miyaura Cross-Coupling of 1,8-Diaminonaphthalene (dan)-Protected Arylboronic Acids
作者:Yuichiro Mutoh、Kensuke Yamamoto、Shinichi Saito
DOI:10.1021/acscatal.9b03667
日期:2020.1.3
Suzuki–Miyaura cross-coupling reaction of 1,8-diaminonaphthalene (dan)-protected arylboronicacids in the presence of KOt-Bu, which does not require the removal of the dan moiety. Notably, the use of aryl-B(dan) in the Suzuki–Miyaura reaction provides a complementary solution to the protodeboronation problems. The base KOt-Bu plays a crucial role for the promotion of these cross-coupling reactions as
我们报道了在存在KO t -Bu的情况下1,8-二氨基萘(dan)保护的芳基硼酸的Suzuki-Miyaura交叉偶联反应,该反应不需要去除dan部分。值得注意的是,在Suzuki-Miyaura反应中使用芳基-B(dan)可为原脱硼问题提供补充解决方案。碱KO t -Bu在促进这些交叉偶联反应中起着至关重要的作用,因为它能够形成硼酸盐。该反应方案扩展到了4-[((pin)B] C 6 H 4 -B(dan)的一锅顺序Suzuki-Miyaura交叉偶联反应,其中“反应性较低”的芳基-B(dan)部分优先交叉耦合。