已开发出在室温(rt)和无过渡金属条件下进行N-和O-磺酰化的新方法。第一种方法涉及在室温下仅使用二甲基亚砜(DMSO)中的KO t Bu将各种N-磺酰基杂环和苯基苯磺酸盐以良好或优异的收率转化为相应的脱磺酰化产物。或者,已经使用可见光方法用作为可见光吸收剂的Hantzsch酯(HE)阴离子和电子和氢原子供体来促进N-甲基-N-芳基磺酰胺的脱保护,以促进脱磺酰化反应。HE阴离子可轻松就地制备通过在室温下将相应的HE与DMSO中的KO t Bu反应。进一步研究了两种方案的合成范围和机制方面,以合理化脱磺酰化工艺的关键特征。此外,HE阴离子在可见光照射下诱导芳基卤化物的还原脱卤反应。
A one-potthree-componentreaction involving nitroarenes, (hetero)arylboronic acids, and potassium pyrosulfite leading to sulfonamides was described. A broad range of sulfonamides bearing different reactive functional groups were obtained in good to excellent yields through sequential C-S and S-N coupling that does not require metal catalysts.
Highly Effective Pd-Catalyzed ortho Olefination of Acetanilides: Broad Substrate Scope and High Tolerability
作者:Byung Seok Kim、Chungsik Jang、Dong Jin Lee、So Won Youn
DOI:10.1002/asia.201000613
日期:2010.11.2
Bring it on! An effective Pd‐catalyzed orthoolefination of various acetanilides has been developed. This transformation has a broadsubstratescope and wide functional‐group tolerability, regardless of the electronic and steric properties of acetanilidesubstrates, providing a straightforward access to highly functionalized arenes.
Pd-Catalyzed Sequential CC and CN Bond Formations for the Synthesis of N-Heterocycles: Exploiting Protecting Group-Directed CH Activation under Modified Reaction Conditions
作者:Byung Seok Kim、Sun Young Lee、So Won Youn
DOI:10.1002/asia.201100024
日期:2011.8.1
addition reaction of N‐Ts‐2‐arylanilines with activated olefins has been achieved at ambient temperature under the newly defined reaction conditions. This process highlighted the directing effect of the N‐protecting group in CHactivation, displayed broad substrate scope with wide functional group compatibility; thus rendering a straightforward entry to a wide variety of N‐heterocycles such as d
Palladium‐Catalyzed and Hybrid Acids‐Assisted Synthesis of [60]Fulleroazepines in One Pot under Mild Conditions: Annulation of
<i>N</i>
‐Sulfonyl‐2‐aminobiaryls with [60]Fullerene through Sequential C‐H Bond Activation, C‐C and C‐N Bond Formation
An extraordinarily efficient hybrid acids‐assisted, palladium‐catalyzed and chelating‐group‐assisted CH bond activation of N‐sulfonyl‐2‐aminobiaryls and their annulations with [60]fullerene via sequential CC and CN bond formation at room temperature to afford [60]fulleroazepines is demonstrated. The formation of [60]fulleroazepines is highly regioselective and tolerant to both electron‐withdrawing
Intramolecular Oxidative C−N Bond Formation for the Synthesis of Carbazoles: Comparison of Reactivity between the Copper-Catalyzed and Metal-Free Conditions
作者:Seung Hwan Cho、Jungho Yoon、Sukbok Chang
DOI:10.1021/ja111652v
日期:2011.4.20
New synthetic procedures for intramolecular oxidative C-N bondformation have been developed for the preparation of carbazoles starting from N-substituted amidobiphenyls under either Cu-catalyzed or metal-freeconditions using hypervalent iodine(III) as an oxidant. Whereas iodobenzene diacetate or bis(trifluoroacetoxy)iodobenzene alone undergoes the reaction to provide carbazole products in moderate
已经开发了用于分子内氧化 CN 键形成的新合成程序,用于在 Cu 催化或无金属条件下使用高价碘 (III) 作为氧化剂从 N 取代的酰氨基联苯制备咔唑。虽然二乙酸碘苯或双(三氟乙酰氧基)碘苯单独进行反应以提供中低收率的咔唑产物,但三氟甲磺酸铜(II)和碘(III)物质的组合使用显着提高了反应效率,提供了更多样化的范围产品良率高。在包括动力学曲线、同位素效应和自由基抑制实验在内的机理研究的基础上,铜物种被提议用于催化激活高价碘 (III) 氧化剂。