base-mediated hydroamination protocol, using substoichiometric amounts of a hydrosilane and potassium tert-butoxide, that operates under mild conditions at 30 °C. Many aryl- and heteroatom-substituted olefins as well as arylamines are tolerated, affording the desired products with complete regioselectivity. Preliminary mechanistic investigations reveal a non-radical pathway for hydroamination. A sequential
我们提出了一种碱介导的加氢胺化方案,使用亚化学计量的氢硅烷和叔丁醇钾,在 30°C 的温和条件下运行。可以耐受许多芳基和杂原子取代的烯烃以及芳基胺,从而提供具有完全区域选择性的所需产物。初步的机理研究揭示了加氢胺化的非自由基途径。还开发了一种顺序远程加氢胺化策略,包括初始 Fe 催化的烯烃异构化,然后是我们的碱介导的加氢胺化,以直接从末端脂肪族烯烃中获取 β-芳基胺。
Iron-Catalyzed Regioselective α-C–H Alkylation of <i>N</i>-Methylanilines: Cross-Dehydrogenative Coupling between Unactivated C(sp<sup>3</sup>)–H and C(sp<sup>3</sup>)–H Bonds via a Radical Process
作者:Ze-Lin Li、Kang-Kang Sun、Peng-Yu Wu、Chun Cai
DOI:10.1021/acs.joc.9b00625
日期:2019.6.7
without any directing group by cross-dehydrogenative coupling between unactivatedC(sp3)–H and C(sp3)–Hbonds has been established for the first time, which provides a good complement to C(sp3)–Hactivation reactions and expands the field of Fe-catalyzed C–H functionalizations. Many different C(sp3)–Hbonds in cyclic alkanes, cyclic ethers, and toluene derivatives can be used as coupling partners. Mechanistic
selective methods, but the re- action conditions are somewhat harsh, as strong reducing reagents must be used. Nowadays, the formation of C-N bonds via cross- coupling reactions is an essential methodology for the preparation of nitrogen-containing compounds. Recently, different transition-metal-promoted reactions have been developed for the synthesis of secondary amines: catalytic systems for N-alkylation
介绍了一种简单的铜促进的苯胺 N-单烷基化,它利用烷基硼酸作为烷基化伙伴。该反应在回流的二恶烷中进行,它允许在一个步骤中对许多结构和电子不同的苯胺进行官能化。进行了广泛的研究以证明这种新方法在制备苯乙基苯胺方面的实用性。芳香胺是生物活性化合物,广泛存在于制药和农业化学工业中。1 因此,开发新的合成方法仍然是一个活跃的研究领域。特别吸引人的是广泛使用的初级苯胺转化为相应的次级苯胺。直接烷基化通常通过在碱存在下与烷基卤或类似试剂反应来完成。这似乎是一个简单的转化,但在许多情况下,由于过度烷基化,伯苯胺的有效 N-单烷基化是不可能的,这会提供叔苯胺或季铵盐作为副产物。其他制备单烷基化苯胺的方法基于使用允许引入单个烷基的临时保护基团(例如氨基甲酸酯、苄基),然后去除保护基团(引入两个额外的步骤)过程)。然而,由于它们的毒性,必须避免使用许多烷化剂,尤其是在 API 和活性化合物合成的最后一步。羰基
Preparation of N-arylamines from 2-oxo-7-azobicyclo[4.1.0]heptanes
作者:M. Teresa Barros、Suvendu S. Dey、Christopher D. Maycock、Paula Rodrigues
DOI:10.1016/j.tet.2012.05.054
日期:2012.8
A wide range of N-phenylated secondary amines were prepared directly from 2-oxo-7-azobicyclo[4.1.0]heptanes using 4-nitrobenzoic acid as acid catalyst. The intermediate enol esters could also be isolated under similar conditions. A catalytic cycle is proposed.
report an efficient Buchwald–Hartwig cross-couplingreaction in alcoholic solvent, in which a low catalystloading showed excellent performance for coupling aryl halides (I, Br, and Cl) with a broad set of amines, amides, ureas, and carbamates under mild conditions. Mechanistically speaking, in a protic and polar medium, extremely bulky biarylphosphine ligands interact with the dimeric precatalyst
我们报告了一种在醇溶剂中进行的高效 Buchwald-Hartwig 交叉偶联反应,其中低催化剂负载量显示了芳基卤化物(I、Br 和 Cl)与多种胺、酰胺、脲和氨基甲酸酯在条件温和。从机理上讲,在质子和极性介质中,极其庞大的联芳基膦配体与二聚体预催化剂 [Pd(π-( R )-allyl)Cl] 2相互作用形成相应的阳离子配合物 [Pd(π-( R )-allyl) (L)]Cl原位并且自发地。所得预催化剂在碱性条件下进一步演化为相应的 L-Pd(0) 催化剂,该催化剂通常用于交叉偶联反应。这项机理研究强调了醇类溶剂在活性催化剂形成中的突出作用。