Thiophenols as Protic Nucleophilic Triggers in Aryne Three-Component Coupling
作者:Subrata Bhattacharjee、Avishek Guin、Rahul N. Gaykar、Akkattu T. Biju
DOI:10.1021/acs.orglett.0c03494
日期:2020.11.20
The synthetic potential of thiophenols as a protic nucleophilic trigger in the transition-metal-free and Grignard-reagent-free three-component coupling involvingarynes is demonstrated. Employing aldehydes as the third component, the reaction allowed the mild and broad scope synthesis of 2-arylthio benzyl alcohol derivatives in good yields. Moreover, selenophenol could be used as the nucleophilic trigger
Trifluoromethyl Benzoate: A Versatile Trifluoromethoxylation Reagent
作者:Min Zhou、Chuanfa Ni、Yuwen Zeng、Jinbo Hu
DOI:10.1021/jacs.8b04000
日期:2018.6.6
Trifluoromethyl benzoate (TFBz) is developed as a new shelf-stable trifluoromethoxylation reagent, which can be easily prepared from inexpensive starting materials using KF as the only fluorine source. The synthetic potency of TFBz is demonstrated by trifluoromethoxylation-halogenation of arynes, nucleophilic substitution of alkyl (pseudo)halides, cross-coupling with aryl stannanes, and asymmetric
spirocyclization forming spirooxindoles and spirodihydrobenzofurans has been achieved. Mechanistic studies suggest that the transformation proceeds through sequential carbopalladation, C–Hactivation, and benzyne insertion. Both classes of spirocycles have been synthesized in good to excellent yields, and the procedure is readily scalable.
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 three-componentcoupling of arynes, aminosilanes, and aldehydes enables diverse amino and hydroxymethyl groups to be incorporated directly into 1,2-positions of aromatic rings.