描述了在氢借位催化下使用1°或2°醇对各种酮进行的烷基化。最初的研究集中在环丙酮与更高的1°醇(即大于MeOH)的α-烷基化反应上,导致形成α-支化产物。我们通过寻找其他底物来探索这种化学反应,使我们发现,二邻位取代的芳基酮也是特有的支架,其中Ph ∗(C 6 Me 5)酮是最佳选择。进一步的研究表明,该基序对于与2°醇形成β支链产物的烷基化至关重要,这也为研究非对映选择性和分子内氢借入过程提供了机会。
Hydrogen borrowing catalysis using 1° and 2° alcohols: Investigation and scope leading to α and β branched products
作者:James R. Frost、Choon Boon Cheong、Wasim M. Akhtar、Dimitri F.J. Caputo、Kirsten E. Christensen、Neil G. Stevenson、Timothy J. Donohoe
DOI:10.1016/j.tet.2021.132051
日期:2021.4
variety of ketonesusing 1° or 2° alcohols under hydrogen borrowing catalysis is described. Initial research focused on the α-alkylation of cyclopropyl ketones with higher 1° alcohols (i.e. larger than MeOH), leading to the formation of α-branchedproducts. Our search for additional substrates with which to explore this chemistry led us to discover that di-ortho-substituted aryl ketones were also privileged
描述了在氢借位催化下使用1°或2°醇对各种酮进行的烷基化。最初的研究集中在环丙酮与更高的1°醇(即大于MeOH)的α-烷基化反应上,导致形成α-支化产物。我们通过寻找其他底物来探索这种化学反应,使我们发现,二邻位取代的芳基酮也是特有的支架,其中Ph ∗(C 6 Me 5)酮是最佳选择。进一步的研究表明,该基序对于与2°醇形成β支链产物的烷基化至关重要,这也为研究非对映选择性和分子内氢借入过程提供了机会。
A Stereoselective Photoinduced Cycloisomerization Inspired by Ophiobolin A
作者:James A. Law、Daniel P. Callen、Elena L. Paola、Gabe Gomes、James H. Frederich
DOI:10.1021/acs.orglett.2c02272
日期:2022.9.16
A stereoselective synthetic entry point to the 5–8–5 carbocyclic core of the ophiobolins was developed. This strategy exploits the chiral tertiary alcohol of ophiobolin A to guide assmebly of the 5–8–5 scaffold in a single step via a photoinitiated cycloisomerization. Mechanistic insights into the origin of stereocontrol in this reaction are described, as are efforts to elaborate the resultant fused
开发了 ophiobolins 5-8-5 碳环核心的立体选择性合成入口点。该策略利用 ophiobolin A 的手性叔醇通过光引发环异构化一步引导 5-8-5 支架的组装。描述了对该反应中立体控制起源的机制见解,以及将所得的 5-8-5 环稠合系统与 ophiobolin A 药效团详细阐述的努力。