Various 2-alkylidenethietanes were synthesized by intramolecular nucleophilicsubstitution reactions at an sp2 carbon of vinyl halides with thiolate moieties. The reaction pathway of the substitution reactions was confirmed as a very rare SNVπ mechanism by theoretical and experimental studies.
Easily accessible non-aromatic heterocycles with handles: 4-bromo-2,3-dihydrofurans from 1,2-dibromohomoallylic alcohols
作者:Jason An、Jose Intano、Alissa Richard、Taehyun Kim、José A. Gascón、Amy R. Howell
DOI:10.1039/d1sc01013a
日期:2021.8.4
3-dihydrofurans is reported. These non-aromatic heterocycles containing a useful coupling handle are accessed via Cu-catalyzed intramolecular cyclization of 1,2-dibromohomoallylic alcohols, which are themselves available in just two steps from aromatic and aliphatic aldehydes and ketones. Molecular dynamics simulations using the simple substrates and key geometric parameters provide a rationale for the selectivities
Preference of 4-<i>exo</i> Ring Closure in Copper-Catalyzed Intramolecular Coupling of Vinyl Bromides with Alcohols
作者:Yewen Fang、Chaozhong Li
DOI:10.1021/ja072793w
日期:2007.7.1
2-methyleneoxetanes in good to excellent yields via a 4-exo ringclosure. The configuration of the CC bond was nicely retained. This methodology was then successfully extended to the cyclization in 5-exo, 6-exo, and even 6-endo modes. Moreover, the competition experiments revealed that 4-exo cyclization is fundamentally preferred over other modes of cyclization. On the other hand, the corresponding Pd(0)-catalyzed
This article presents a full account of intramolecular vinylic substitution reactions of bromoalkenes having an acetylthio moiety, which give sulfur-containing heterocycles such as dihydrothiophene, tetrahydrothiopyran, and 2-alkylidenethietane derivatives. The reaction pathways of the substitution reactions were investigated by theoretical and experimental studies.