Electrochemical Nozaki–Hiyama–Kishi Coupling: Scope, Applications, and Mechanism
作者:Yang Gao、David E. Hill、Wei Hao、Brendon J. McNicholas、Julien C. Vantourout、Ryan G. Hadt、Sarah E. Reisman、Donna G. Blackmond、Phil S. Baran
DOI:10.1021/jacs.1c03007
日期:2021.6.30
practical using an electroreductive manifold. Although early studies pointed to the feasibility of such a process, those precedents were never applied by others due to cumbersome setups and limited scope. Here we show that a carefully optimized electroreductive procedure can enable a more sustainable approach to NHK, even in an asymmetric fashion on highly complex medicinally relevant systems. The e-NHK
最常用的 C-C 键形成方法之一是使用还原歧管,使卤乙烯与 Ni 和 Cr 催化的醛偶联(Nozaki-Hiyama-Kishi,NHK)变得更加实用。尽管早期研究指出了这种过程的可行性,但由于设置繁琐且范围有限,这些先例从未被其他人应用。在这里,我们展示了经过精心优化的电还原程序可以使 NHK 采用更可持续的方法,即使在高度复杂的医学相关系统上以不对称方式也是如此。当传统化学技术失败时,e-NHK 甚至可以使非规范底物类别(例如氧化还原活性酯)参与低负载量的 Cr。详细的动力学、循环伏安法、
Ni-Catalyzed Cross-Electrophile Coupling for the Synthesis of Skipped Polyenes
作者:Catherine P. McGeough、Alexandra E. Strom、Timothy F. Jamison
DOI:10.1021/acs.orglett.9b01019
日期:2019.5.17
Skipped polyenes featuring high ( E)-selectivity and varying methyl substitution patterns are synthesized using a nickel-catalyzed cross-coupling reaction between allyl trifluoroacetates and vinyl bromides. The utility of this cross-electrophile coupling is showcased in part by the synthesis of the RST fragment of the marine ladder polyether, maitotoxin. Construction of this fragment is particularly
Highly Efficient Transfer of Chirality from Macrocyclic Conformation in the Tandem Oxy-Cope/Claisen/Ene Reaction
作者:Effiette L. O. Sauer、Louis Barriault
DOI:10.1021/ja048301m
日期:2004.7.14
We report three highly stereoselective pericyclic reactions occurring in cascade leading to the synthesis of Decalins skeletons possessing two contiguous quaternary centers. The tandem reaction is triggered by an oxy-Cope rearrangement to create in situ a 10-membered ring enol ether macrocyle 6, which immediately rearranges via a Claisen [3,3] shift to the corresponding E-cyclodec-6-en-1-one 7. The
Total Synthesis of Dumsin. 1. Retrosynthetic Strategy and the Elaboration of Key Intermediates from (−)-Bornyl Acetate
作者:Leo A. Paquette、Fang-Tsao Hong
DOI:10.1021/jo0301346
日期:2003.9.1
An intramolecular anionic oxy-Cope rearrangement (44 --> 46) serves as the key step in a synthetic approach to the insect antifeedant dumsin. Initial investigations clarified the manner in which (--)-bornyl acetate may be transformed into the exo-norbornenol 44. Two routes were developed to advance beyond 46. The first involved acetal 51 as a matrix that was expected to allow the elaboration of rings
The first total synthesis of crassostreaxanthin B 1 was accomplished via the tetrasubstituted olefinic compound 5, prepared by stereoselective rearrangement of epoxides 3a,b using a Lewis acid.
首次全面合成crassostreaxanthin B 1是通过使用路易斯酸对环氧化物3a,b进行立体选择性重排所制备的四取代烯烃化合物5完成的。