Kinetics of the reactions of bissulfonylethylenes with various carbanions, a sulfur ylide, and siloxyalkenes have been investigated photometrically at 20 °C. The second‐order rate constants have been combined with the known nucleophile‐ specific parameters N and sN for the nucleophiles to calculate the empirical electrophilicity parameters E of bissulfonylethylenes according to the linear free energy
双磺酰基乙烯与各种碳负离子,硫叶立德和甲硅烷氧基烯烃的反应动力学已在20°C下进行了光度法研究。将二阶速率常数与亲核试剂的已知亲核试剂特定参数N和s N相结合,以根据线性自由能关系log k(20°C)= s N计算双磺酰基乙烯的经验亲电参数E(N + E)。讨论了结构-反应关系,并表明亲电参数E 这项工作中衍生的衍生物可用于定义双磺酰基乙烯作为Michael受体的合成潜力。
Rigidified Bis(sulfonyl)ethylenes as Effective Michael Acceptors for Asymmetric Catalysis: Application to the Enantioselective Synthesis of Quaternary Hydantoins
作者:Leire Villaescusa、Iker Hernández、Laura Azcune、Ainhoa Rudi、José M. Mercero、Aitor Landa、Mikel Oiarbide、Claudio Palomo
DOI:10.1021/acs.joc.2c02403
日期:2023.1.20
diastereoselective addition of hydantoin surrogates II to “rigidified” vinylidene bis(sulfone) reagents is developed, thus overcoming the inability of commonly employed β-substituted vinylic sulfones to react. Adducts are transformed in enantioenriched 5,5-disubstituted hydantoins through hydrolysis and reductive desulfonylation processes providing new structures for eventual bioassays. Density functional theory studies