Catalytic Nucleophilic Fluorination of Secondary and Tertiary Propargylic Electrophiles with a Copper-N-Heterocyclic Carbene Complex
作者:Li-Jie Cheng、Christopher J. Cordier
DOI:10.1002/anie.201506882
日期:2015.11.9
A catalytic method for the nucleophilicfluorination of propargylicelectrophiles is described. Our protocol involves the use of a Cu(NHC) complex as the catalyst and is suitable for the preparation of secondary and tertiarypropargylic fluorides without the formation of isomeric fluoroallenes. Preliminary mechanistic investigations suggest that fluorination proceeds via copper acetylides and that
Intramolecular Capture of HDDA-Derived Benzynes: (i) 6- to 12-Membered Ring Formation, (ii) Internally (vis-à-vis Remotely) Tethered Traps, and (iii) Role of the Rate of Trapping by the Benzynophile
作者:Yuanxian Wang、Thomas R. Hoye
DOI:10.1021/acs.orglett.7b03436
日期:2018.1.5
hexadehydro-Diels–Alder reaction of substrates containing tethered trapping moieties. Products having new structural motifs can be created. (i) Medium-sized fused rings can be produced by varying the length of the tether. (ii) The tether can emanate from an atom within the linker unit that joins the 1,3-diyne and diynophile. (iii) The importance of the rate of trapping by the benzynophile is established.
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。