Herein, we disclose a transition-metal-free reaction system that enables α-cyanation of sulfonamides through C–H bond cleavage for the preparation of α-amino nitriles, including difficult-to-access all-alkyl α-tertiary scaffolds. More than 50 substrate examples prove a wide functional group tolerance. Additionally, its synthetic practicality is highlighted by gram-scalability and the late-stage modification
Sulfonyl Azides as Precursors in Ligand-Free Palladium-Catalyzed Synthesis of Sulfonyl Carbamates and Sulfonyl Ureas and Synthesis of Sulfonamides
作者:Shiao Y. Chow、Marc Y. Stevens、Luke R. Odell
DOI:10.1021/acs.joc.5b02755
日期:2016.4.1
An efficientsynthesis of sulfonyl carbamates and sulfonyl ureasfrom sulfonyl azides employing a palladium-catalyzed carbonylation protocol has been developed. Using a two-chamber system, sulfonyl azides, PdCl2, and CO gas, released ex situ from Mo(CO)6, were assembled to generate sulfonyl isocyanates in situ, and alcohols and aryl amines were exploited as nucleophiles to afford a broad range of sulfonyl
TiCl4-Mediated Direct N-Alkylation of Sulfonamides with Inactive Ethers
作者:Wei Zeng、Jiayan Chen、Ling Dang、Qiang Li、Yong Ye、Shaomin Fu
DOI:10.1055/s-0031-1290332
日期:2012.3
A TiCl4-mediated intermolecular or intramolecular direct N-alkylationreaction of sulfonamides with inactive ethers as alkylating agents was successfully achieved. This method provides a novel approach towards N-alkyl sulfonamides from inactive ethers via an easy workup procedure. N-alkylation - Lewis acid - N-alkyl sulfonamide - dialkyl ether - titanium tetrachloride
Liganding Functional Tyrosine Sites on Proteins Using Sulfur–Triazole Exchange Chemistry
作者:Jeffrey W. Brulet、Adam L. Borne、Kun Yuan、Adam H. Libby、Ku-Lung Hsu
DOI:10.1021/jacs.0c00648
日期:2020.5.6
LG for activating nucleophilic substitution reactions on tyrosine sites of proteins. Here, we probed tunability of SuTEx for fragment-based liganddiscovery by modifying the adduct group (AG) and LG with functional groups of differing electron-donating and -withdrawing properties. We discovered the sulfur electrophile is highly sensitive to the position of modification (AG versus LG), which enabled both
Experimental and Computational Studies on Cp*<sup>Cy</sup>Rh(III)/KOPiv-Catalyzed Intramolecular Dehydrogenative Cross-Couplings for Building Eight-Membered Sultam/Lactam Frameworks
作者:Liping Li、Hui Gao、Ming Sun、Zhi Zhou、Wei Yi
DOI:10.1021/acs.orglett.0c01823
日期:2020.7.17
is an unusual Cp*CyRh(III)-catalyzed intramolecular site-specific aryl C–H annulation, a highly chemoselective protocol providing direct access to eight-membered sultams/lactams with broad substrate/functional group tolerance. Experimental and computational studies reveal that such a transformation involves a unique PivOH-assisted aryl C–H activation/alkene insertion/β-H elimination/hydrogen-transfer