Palladium-catalyzed dicyanative [4 + 2] cycloaddition using various ene−enynes was investigated. The key species in this process is a cyanoallene intermediate that is obtained by the cyanopalladation of conjugated enynes followed by 5-exo-cyclization. To achieve an efficient [4 + 2] cycloaddition reaction, both the smooth generation of this species and critical control of regioselectivity in the 6-endo-cyclization
An efficient, quantitative deracemization strategy for optically inactive allylic cycloalkanols has been achieved using the biphasic halogenative semi-pinacol reaction protocol. The resultant β-halo spiroketones, containing three contiguous stereogenic centers, were easily recovered with high diastereomeric and enantiomeric purities following conventional silica gel chromatography. The optically active products could be further manipulated chemically, affording synthetically interesting scaffolds with complete preservation of stereoisomeric integrity.
Provided herein are compounds that are useful in the treatment of pain in a subject.
提供在本文件中的化合物可用于治疗主体的疼痛。
Total Synthesis of Gelsemoxonine through a Spirocyclopropane Isoxazolidine Ring Contraction
作者:Stefan Diethelm、Erick M. Carreira
DOI:10.1021/jacs.5b02574
日期:2015.5.13
of this plant incorporating a highlyfunctionalized azetidine at its core. We herein report a full account of our studies directed toward the totalsynthesis of gelsemoxonine that relies on a conceptually new approach for the construction of the central azacyclobutane. A spirocyclopropane isoxazolidine ring contraction was employed to access a key β-lactam intermediate, which could be further elaborated
Enantioselective Synthesis of Cyclopropanone Equivalents and Application to the Formation of Chiral β‐Lactams
作者:Christopher M. Poteat、Yujin Jang、Myunggi Jung、J. Drake Johnson、Rachel G. Williams、Vincent N. G. Lindsay
DOI:10.1002/anie.202006786
日期:2020.10.12
derivatives have long been considered unsustainable synthetic intermediates because of their extreme strain and kinetic instability. Reported here is the enantioselective synthesis of 1‐sulfonylcyclopropanols, as stable yet powerful equivalents of the corresponding cyclopropanone derivatives, by α‐hydroxylation of sulfonylcyclopropanes using a bis(silyl) peroxide as the electrophilic oxygen source. This