An Umpolung Oxa-[2,3] Sigmatropic Rearrangement Employing Arynes for the Synthesis of Functionalized Enol Ethers
作者:Rahul N. Gaykar、Malini George、Avishek Guin、Subrata Bhattacharjee、Akkattu T. Biju
DOI:10.1021/acs.orglett.1c00911
日期:2021.5.7
An oxa-[2,3] sigmatropicrearrangement involving arynes is reported featuring the umpolung of ketones, where the C═O bond polarity is reversed. The in situ-generated sulfur ylides from β-keto thioethers and arynes undergo efficient rearrangement allowing the facile and robust synthesis of functionalized enol ethers in high yields and excellent functional group compatibility. Preliminary mechanistic
A method of preparing 3,4-ethylenedioxythiophene is provided. The preparation is performed by microwave heating to greatly increase the yield and decrease the reaction time, energy consumption, solvent usage, and environmental damage.
Chemoenzymatic Cascades for the Enantioselective Synthesis of β‐Hydroxysulfides Bearing a Stereocentre at the C−O or C−S Bond by Ketoreductases
作者:Fei Zhao、Kate Lauder、Siyu Liu、James D. Finnigan、Simon B. R. Charnock、Simon J. Charnock、Daniele Castagnolo
DOI:10.1002/anie.202202363
日期:2022.8
Four ketoreductases (KREDs) were identified for the enantioselectivesynthesis of β-hydroxysulfides. KRED311 and KRED349 catalyse the synthesis of β-hydroxysulfides bearing a stereocentre at the C−Obond with opposite absolute configurations via chemoenzymaticcascades from thiophenols/thiols and α-haloketones/alcohols. KRED253 and KRED384 catalyse the synthesis of β-hydroxysulfides bearing a stereocentre