从概念上讲,细胞毒性海洋天然产物 njaoamine C 的首次全合成不同于所有已知的曼扎明超家族相关生物碱的方法,因为包封二氮杂三环核心的两个大环是同时形成的。这一目标是通过双环闭炔复分解(dRCAM)实现的。这一操作的成功不仅反映了需要以适当的成对方式连接的四个炔链的有利预取向,而且也是动态共价化学的结果,涉及所选“冠层”钼烷炔催化剂的纠错。dRCAM 下游的最终游戏利用了钯催化氢化锡化的惊人化学选择性,即使存在空间上更容易接近的二烷基炔或烯烃,它也会选择(杂)芳基炔;对于这种偏好,该方法补充了加氢金属化和半还原反应的经典方法。
Asymmetric Alkyl−Alkyl Cross-Couplings of Unactivated Secondary Alkyl Electrophiles: Stereoconvergent Suzuki Reactions of Racemic Acylated Halohydrins
作者:Nathan A. Owston、Gregory C. Fu
DOI:10.1021/ja105924f
日期:2010.9.1
A method for asymmetric alkyl-alkylSuzuki reactions of unactivatedsecondaryalkyl electrophiles, specifically, cross-couplings of racemic acylated halohydrins with alkylborane reagents, has been developed. A range of protected bromohydrins, as well as a protected chlorohydrin and a homologated bromohydrin, are coupled in good ee by a catalyst derived from commercially available components.
已开发出一种用于未活化仲烷基亲电试剂的不对称烷基-烷基 Suzuki 反应的方法,特别是外消旋酰化卤代醇与烷基硼烷试剂的交叉偶联。一系列受保护的溴醇,以及受保护的氯醇和同系溴醇,通过衍生自市售组分的催化剂以良好的 ee 偶联。
Alkyl-Alkyl Suzuki Cross-Coupling of Unactivated Secondary Alkyl Chlorides
作者:Zhe Lu、Gregory C. Fu
DOI:10.1002/anie.201003272
日期:2010.9.3
reaction designed specifically for the title substrates CC coupling with alkyl boranes occurred in good yield at room temperature with commercially available catalyst components (see scheme). This versatile method is also suitable for Suzuki reactions of secondary and primary alkyl bromides and iodides, as well as primary alkylchlorides.
没有问题基材之类的东西!在专门为标题底物设计的反应中,C C 与烷基硼烷偶联,在室温下使用市售催化剂组分以良好的产率发生(参见方案)。这种通用方法也适用于仲和伯烷基溴化物和碘化物以及伯烷基氯化物的 Suzuki 反应。
Palladium-Catalyzed Carbonylative Cross-Coupling of Difluoroalkyl Halides with Alkylboranes under 1 atm of CO
作者:Hai-Yang Zhao、Minqi Zhou、Xingang Zhang
DOI:10.1021/acs.orglett.1c03396
日期:2021.12.3
A palladium catalyzed carbonylative cross-coupling of difluoroalkyl halides with alkyl-9-BBN under 1 atm of CO has been developed. The reaction shows broad substrate scope and high functional group tolerance, even toward complex pharmaceuticals, providing a general and straightforward method to access alkyldifluoroalkyl ketones. Preliminary mechanistic studies reveal that a radical pathway is involved
已开发出钯催化的二氟烷基卤化物与烷基-9-BBN 在 1 个大气压的 CO 下的羰基化交叉偶联。该反应显示出广泛的底物范围和高官能团耐受性,甚至对复杂的药物也是如此,为获取烷基二氟烷基酮提供了一种通用且直接的方法。初步的机理研究表明,该反应涉及自由基途径。
Total Synthesis of Aphadilactones A–D
作者:Jian-Peng Yin、Min Gu、Ying Li、Fa-Jun Nan
DOI:10.1021/jo501117k
日期:2014.7.3
The first total synthesis of aphadilactones A-D, diastereomeric natural products recently isolated from the Meliaceae plant Aphanamixis grandifolia by Yue and co-workers, which possess an unprecedented carbon skeleton, has been achieved. The synthesis features a catalytic asymmetric hetero-Diels-Alder reaction to form the dihydropyran ring, concurrent installation of the lactone and furan moieties via a tandem acid-catalyzed acetal cleavage, oxidation, and cyclization process, and an intermolecular Diels-Alder reaction to forge the target products.