Mechanistic Dichotomy with Alkynes in the Formal Hydrohydrazination/Fischer Indolization Tandem Reaction Catalyzed by a Ph3PAuNTf2/pTSA Binary System
作者:Nitin T. Patil、Ashok Konala
DOI:10.1002/ejoc.201001114
日期:2010.12
method involving a formalhydrohydrazination/ Fischerindolizationtandemreaction to synthesize 2,3-disubstituted indoles from alkynes and arylhydrazines has been developed. The approach uses a Ph 3 PAuNTf 2 /pTSA·H 2O binary catalytic system in which a very low catalyst loading of Ph 3 PAuNTf 2 (2 mol-%) is required. The reaction time is very short and, most importantly, the reaction is not sensitive
assembly of benzo[c]carbazole derivatives via the Diels–Alder reaction of arynes and easily accessible 2-alkenylidoles was reported. By employing different aryne precursor loads, 6,7-dihydrobenzo[c]carbazoles or aryl-substituted 7,11b-dihydrobenzo[c]carbazoles could be controllably generated in good to excellent yields under a nitrogen atmosphere. On the other hand, when the reaction was conducted under
据报道,苯并[ c ]咔唑衍生物可通过芳烃和易于接近的2-烯基基团的狄尔斯-阿尔德反应直接组装。通过使用不同的芳烃前体负载量,可以在氮气氛下以良好至优异的产率可控制地生成6,7-二氢苯并[ c ]咔唑或芳基取代的7,11b-二氢苯并[ c ]咔唑。另一方面,当反应在氧气下进行时,可以一步一步地以高选择性和高效率直接生成氧化/芳构化产物苯并[ c ]咔唑。有趣的是,苯并[ c上述产物的]咔唑-5-羧酰胺酰胺化衍生物显示出良好的抗肿瘤活性。还描述了这些分子对癌细胞的抑制作用。
Synthesis of Indole Substituted Twistenediones from a 2-Quinonyl Boronic Acid
作者:Jaime Rojas-Martín、Marcos Veguillas、María Ribagorda、M. Carmen Carreño
DOI:10.1021/ol402689b
日期:2013.11.15
Indole substituted twistane-like derivatives resulted in a reaction between 3,5-dimethyl-2-quinonyl boronic acid and 2-alkenyl indoles. Their MCPBA oxidation gave 6/6/9 caged systems. Boronic acid acts as a temporal promoter allowing a site-selective conjugate addition of the heteroaromatic system to the methyl substituted C-3 quinone carbon, giving an intermediate diene which is regioselectively trapped
One-pot access to tetrahydrobenzo[<i>c</i>]carbazoles from simple ketones by using O<sub>2</sub> as an oxidant
作者:Shuvendu Saha、Modhu Sudan Maji
DOI:10.1039/c9ob02751c
日期:——
diversely functionalized carbazole frameworks starting from protecting group free 2-alkenyl indoles. The employment of easily available unactivated ketones as annulating partners, mostly unexplored for the synthesis of carbazoles, is the major highlight of this protocol. This protocol is step- and atom-economical, uses molecular oxygen as the green oxidant, and gives water as the only by-product and is amenable
Regioselective C−H Functionalization Directed by a Removable Carboxyl Group: Palladium-Catalyzed Vinylation at the Unusual Position of Indole and Related Heteroaromatic Rings
The palladium-catalyzed oxidative vinylation of indole-3-carboxylic acids with alkenes effectively proceeds via directedC-H functionalization and decarboxylation to produce the corresponding 2-vinylated indoles. Similarly, pyrrole-, furan-, and thiophenecarboxylic acids also undergo decarboxylative vinylation.