Enantioselective C–C cross-coupling of unactivated alkenes
作者:Zi-Chao Wang、Xiaohua Luo、Jia-Wen Zhang、Chen-Fei Liu、Ming Joo Koh、Shi-Liang Shi
DOI:10.1038/s41929-023-01037-9
日期:——
carbonickelation and in situ trapping with nucleophiles enable efficient hydrofunctionalization and dicarbofunctionalization of unactivated alkenes in a directing group-free manner. Nickelcatalysts bearing bulky C2-symmetric chiral N-heterocyclic carbene ligands were crucial for attaining high reactivity and selectivity. This strategy offers a general, modular and divergent platform for rapidly upgrading
几十年来,金属催化的交叉偶联在现代化学合成中发挥着核心作用。未活化的烯烃,包括轻质烯烃,在石油工业中被大规模生产,是制备药物、农用化学品和材料的理想起始材料。然而,未活化烯烃的对映选择性交叉偶联仍然是一个具有挑战性的长期目标。在这里,我们报道了未活化烯烃与芳基(或烯基)三氟甲磺酸酯和有机金属(或还原剂)的高度对映和区域选择性三组分交叉偶联,以构建不同的 C sp 3通过镍催化形成立构中心。具体来说,选择性碳镍化和亲核试剂的原位捕获能够以无导向基团的方式对未活化的烯烃进行有效的氢官能化和二碳官能化。带有大体积C 2对称手性N-杂环卡宾配体的镍催化剂对于获得高反应性和选择性至关重要。该策略提供了一个通用、模块化和发散的平台,用于将原料烯烃快速升级为各种增值分子,并有望激发其他具有挑战性的对映选择性烯烃交叉偶联的开发。
A Bimolecular Homolytic Substitution-Enabled Platform for Multicomponent Cross-Coupling of Unactivated Alkenes
The construction of C(sp3)–C(sp3) bonds remains one of the most difficult challenges in cross-coupling chemistry. Here, we report a photoredox/nickel dual catalytic approach that enables the simultaneous formation of two C(sp3)–C(sp3) linkages via trimolecular cross-coupling of alkenes with alkyl halides and hypervalent iodine-based reagents. The reaction harnesses a bimolecular homolytic substitution
[EN] METHODS OF BORYLATION AND USES THEREOF<br/>[FR] PROCÉDÉS DE BORYLATION ET LEURS UTILISATIONS
申请人:NAT UNIV SINGAPORE
公开号:WO2021080511A1
公开(公告)日:2021-04-29
The present invention relates, in general terms, to methods of borylation and uses thereof. In particular, the present invention provides a method of borylating an alkene compound by contacting the compound with a boron compound, a Fe pre-catalyst and a protic additive. The borylation occurs at a vicinal (β) position to an electron donating or electron withdrawing moiety of the compound.
1,4-Pentenyne as a Five-Carbon Synthon for Efficient and Selective Syntheses of Natural Products Containing 2,4-Dimethyl-1-penten-1,5-ylidene and Related Moieties by Means of Zr-Catalyzed Carboalumination of Alkynes and Alkenes
作者:Gangguo Zhu、Ei-ichi Negishi
DOI:10.1002/chem.200701512
日期:2008.1
Two highly efficient protocols for enantioselective synthesis of 2,4-dimethyl-1-penten-1,5-ylidene derivatives involve the combined use of the Zr-catalyzed methylalumination of alkynes (ZMA) and the Zr-catalyzed asymmetric carboalumination of alkenes (ZACA). The ZMA/ZACA protocol has been applied to the synthesis of a nafuredin intermediate 14 and a potential intermediate 18 for milbemycin beta 3,