Diastereoselectivity in the triethylamine-catalyzed sulfa-Michael addition of thiols to nitroalkenes: kinetic and thermodynamic control
作者:Jiandong Wang、Ning Chen、Jiaxi Xu
DOI:10.1016/j.tet.2015.04.053
日期:2015.6
sulfa-Michael addition of nitroalkenes and thiols was investigated. The sulfa-Michael addition is kineticcontrol at the beginning and thermodynamiccontrol at the end for less bulky reactants. Thus, kinetic and thermodynamic-controlled adducts can be obtained as major products by controlling the reaction time in those cases. Linear nitroalkenes generally produce anti-adducts as major kinetic products due
Multicomponent Pyrazole Synthesis from Alkynes, Nitriles, and Titanium Imido Complexes via Oxidatively Induced N–N Bond Coupling
作者:Adam J. Pearce、Robin P. Harkins、Benjamin R. Reiner、Alexander C. Wotal、Rachel J. Dunscomb、Ian A. Tonks
DOI:10.1021/jacs.9b13173
日期:2020.3.4
and pharmaceuticals. Pyrazole synthesis often requires hydrazine or related reagents where an intact N-N bond is conservatively installed into a pyrazole precursor fragment. Herein, we report the multicomponent oxidative coupling of alkynes, nitriles, and Ti imidos for the syn-thesis of multisubstituted pyrazoles. This modular method avoids potentially hazardous reagents like hydrazine, instead forming
吡唑是一类重要的杂环,广泛存在于各种生物活性化合物和药物中。吡唑合成通常需要肼或相关试剂,其中完整的 NN 键保守地安装到吡唑前体片段中。在此,我们报告了炔烃、腈和 Ti 亚氨基的多组分氧化偶联,用于合成多取代吡唑。这种模块化方法避免了潜在危险的试剂,如肼,而是在最后一步通过 Ti 上的氧化诱导耦合形成 NN 键。这种转变的机理已经通过关键的二氮杂钛基环己二烯中间体的化学计量反应进行了深入研究,该中间体可以通过 Ti 亚氨基与腈和炔烃的多组分偶联、2-亚氨基-2H-氮丙啶的开环、或通过 4-氮杂二烯-1-胺衍生物的直接金属化。该反应的关键转变是 Ti 上的 2 电子氧化诱导的 NN 耦合。这是金属中心上正式 NN 耦合的罕见例子,它可能通过类似于纳扎罗夫环化的电循环机制发生。方便的是,这些 2-电子氧化的二氮杂钛基环己二烯中间体可以通过 1-电子氧化物质的歧化获得,这允许利用弱氧化剂,如 TEMPO。
Palladium catalyzed synthesis of tertiary allylamines. Utilization of α-nitro olefins as allylic nitro compounds
作者:Rui Tamura、Koji Hayashi、Yoshiki Kai、Daihei Oda
DOI:10.1016/s0040-4039(01)81459-3
日期:1984.1
Reaction of α-nitro olefins with secondary amines in the presence of palladium(O) catalyst affords allylic amines.
在钯(O)催化剂存在下,α-硝基烯烃与仲胺的反应得到烯丙基胺。
Oxidation of nitronates with persulfate and with silver ions
作者:Alfred H. Pagano、Harold Shechter
DOI:10.1021/jo00827a002
日期:1970.2
Scope and Mechanism of "Double-Agent" Halogenation
作者:Franklin P. DeHaan、Matthew W. Allen、Marjorie C. Ang、Donald B. Balacuit、Cornelia A. Bentley、Robert J. Bergstrand、Eugene R. Cho、David O. DeHaan、Timothy E. Farris