and Lu's reagent 1 a being the most reactive and Billard's reagent 1 h being the least reactive electrophile. While the observed electrophilic reactivities (E) of the amido‐derived trifluoromethylthiolating reagents correlate well with the calculated Gibbs energies for heterolytic cleavage of the X−SCF3 bonds (Tt+DA), the cumol‐derivedreagents 1 f and 1 g are more reactive than expected from the thermodynamics
Stereospecific synthesis of [E]-alkenes from enamines via hydroboration
申请人:The Dow Chemical Company
公开号:US04886924A1
公开(公告)日:1989-12-12
A process for the stereospecific synthesis of [E] alkenes from enamines comprising the steps of hydroborating the enamine; esterifying the organoborane so formed and oxidizing the boronic ester in the presence of hydrogen peroxide and in the absence of added base under conditions sufficient to form the [E] alkene in high yield.
Nucleophilic Attack on Nitrogen in Tetrazines by Silyl-Enol Ethers
作者:Simon D. Schnell、Mauro Schilling、Jan Sklyaruk、Anthony Linden、Sandra Luber、Karl Gademann
DOI:10.1021/acs.orglett.0c04113
日期:2021.4.2
The nucleophilic addition of silyl-enol ethers to nitrogen in 3-monosubstituted s-tetrazines mediated by BF3 is reported. The preference for this azaphilic addition over the usually observed inverse electron demand Diels–Alder reactions was evaluated theoretically and corroborated by experiments. The substrate dependency of this unusual reaction was rationalized by determination of the activation barriers
[EN] METHOD FOR THE PREPARATION OF DIARYLISOXAZOLE SULFONAMIDE COMPOUNDS AND INTERMEDIATES<br/>[FR] PROCEDES DESTINES LA PREPARATION D'UN COMPOSE DE DIARYLISOXAZOLE SULFONAMIDE ET D'INTERMEDIAIRES
申请人:PHARMACIA CORP
公开号:WO2005123701A1
公开(公告)日:2005-12-29
The disclosure provides a method for the preparation of a diarylisoxazolé sulfonamide compound comprising contacting a deoxybenzoin with a secondary amine to form a diarylenamine compound; contacting the diarylenamine compound with an acetylating agent to form an acetyl diarylenamine compound; contacting the acetyl diarylenamine compound with a source of hydroxylamine to form an diaryl isoxazolol compound; eliminating water from the diaryl isoxazolol compound to form a diaryl isoxazole compound, chlorosulfonating the diarylisoxazole compound to form a chlorosulfonyl diaryl isoxazole compound; and contacting the chlorosulfonyl diaryl isoxazole compound with a source of ammonia to form the diarylisoxazole sulfonamide compound.
Alkali metal and stoichiometric effects in intermolecular hydroamination catalysed by lithium, sodium and potassium magnesiates
作者:Laia Davin、Alberto Hernán-Gómez、Calum McLaughlin、Alan R. Kennedy、Ross McLellan、Eva Hevia
DOI:10.1039/c9dt00923j
日期:——
neutral Mg(CH2SiMe3)2, even when harsher reaction conditions are employed (24 h, 80 °C). A pronounced alkalimetal effect is also uncovered proving that the alkalimetal (Li, Na, or K) is not a mere spectating counterion. Through stoichiometric reactions, and structural and spectroscopic (DOSY NMR) investigations we shed some light on the potential reaction pathway as well as the constitution of key