Reductive Alkylation of Thioamides with Grignard Reagents in the Presence of Ti(O<i>i</i>Pr)<sub>4</sub>: Insight and Extension
作者:Fabien Hermant、Ewelina Urbańska、Sarah Seizilles de Mazancourt、Thomas Maubert、Emmanuel Nicolas、Yvan Six
DOI:10.1021/om500603v
日期:2014.10.27
thioamides by Grignard reagents in the presence of Ti(OiPr)4 is the subject of a study involving 20 different substrates. The influence of various parameters has been evaluated, showing notably that the yields of this moderately efficient process can be improved in several cases by applying a slow addition of the Grignard reagent. The results presented in this contribution also provide new insight into
Ti(O i Pr)4存在下格氏试剂对硫酰胺的还原烷基化作用是涉及20种不同底物的研究主题。评估了各种参数的影响,值得注意的是,在某些情况下,通过缓慢添加格氏试剂可以提高这种中等有效方法的收率。该贡献中提供的结果也为拟议的关键中间体(即金属化的亚胺基物种和最终的α-金属化的胺)的反应性提供了新的见识。有趣的是,通过控制温度和所结合的格氏试剂的量,该反应可以被导向选择性地形成前一个钛中间体配合物。这代表了原始方法的扩展,允许通过随后添加亲核试剂来合成各种先前难以接近的取代胺。这种作用不仅可以由有机镁化合物发挥作用,而且还可以由烷基锂试剂,烷基钛(IV)络合物和氢化锂铝发挥。还已经研究了α-金属胺最终中间体的性能,表明该络合物是一种不良的亲核试剂,但可以充当自由基前体,这在所得自由基种类稳定后尤其明显。总的来说,这种化学物质被证明是出乎意料的丰富,并且可以为将来开发新的应用奠定基础。证明该络合
One‐Pot Controlled Reduction of Conjugated Amides by Sequential Double Hydrosilylation Catalyzed by an Iridium(III) Metallacycle
effectively the one-pot sequential double hydrosilylation of challenging -unsaturated secondary and tertiary amides to afford in a controlled and straightforward way the corresponding reduced products, that is to say the related secondary and tertiary amides and amines. The catalytic hydrosilylations of the conjugated amides described herein proceeded in good yields and high chemoselectivities. The