25569-79-3Relevant academic research and scientific papers
PIII-Chelation-Assisted Indole C7-Arylation, Olefination, Methylation, and Acylation with Carboxylic Acids/Anhydrides by Rhodium Catalysis
Qiu, Xiaodong,Wang, Panpan,Wang, Dingyi,Wang, Minyan,Yuan, Yu,Shi, Zhuangzhi
supporting information, p. 1504 - 1508 (2019/01/04)
Rhodium-catalyzed C7-selective decarbonylative arylation, olefination, and methylation of indoles with carboxylic acids or anhydrides by C?H and C?C bond activation have been developed. Furthermore, C7-acylation products can also be generated selectively at a lower reaction temperature in the developed system. The key to the high reactivity and regioselectivity of this transformation is the appropriate choice of an indole N-PtBu2 chelation-assisted group. This method has many advantages, including easy access and removal of the directing group, the use of cheap and widely available coupling agents, no requirement of an external ligand or oxidant, a broad substrate scope, high efficiency, and the formation of a sole regioisomer.
Facile and direct synthesis of symmetrical acid anhydrides using a newly prepared powerful and efficient mixed reagent
Rouhi-Saadabad, Hamed,Akhlaghinia, Batool
, p. 479 - 485 (2015/01/30)
An efficient mixed reagent for direct synthesis of symmetrical carboxylic anhydrides from carboxylic acids has been prepared. Carboxylic acids are converted to anhydrides using triphenylphosphine/ trichloroisocyanuric acid under mild reaction conditions at room temperature. Short reaction time, excellent yields of products, low cost, availability of reagents, simple experimental procedure, and easy work-up of the products are the main advantages of the presented method.
Carboxylic acid anhydrides via Pd-catalyzed carbonylation of aryl halides at atmospheric CO pressure
Li, Yang,Xue, Dong,Wang, Chao,Liu, Zhao-Tie,Xiao, Jianliang
supporting information; experimental part, p. 1320 - 1322 (2012/02/04)
A convenient method has been developed, which allows for the direct transformation of aryl iodides into the corresponding carboxylic acid anhydrides via Pd-catalyzed carbonylation under atmospheric CO pressure. The Royal Society of Chemistry 2012.
Sequential O- and N-acylation protocol for high-yield preparation and modification of rotaxanes: Synthesis, functionalization, structure, and intercomponent interaction of rotaxanes
Tachibana, Yuya,Kawasaki, Hiroaki,Kihara, Nobuhiro,Takata, Toshikazu
, p. 5093 - 5104 (2007/10/03)
A pseudorotaxane consisting of a 24-membered crown ether and secondary ammonium salt with the hydroxy group at the terminus was quantitatively acylated by bulky acid anhydride in the presence of tributylphosphane as catalyst to afford the corresponding rotaxane in high yield. Large-scale synthesis without chromatographic separation was easily achieved. The ammonium group in the resulting rotaxane was quantitatively acylated with excess electrophile in the presence of excess trialkylamine. Various N-functionalized rotaxanes were prepared by this sequential double-acylation protocol. 1H NMR spectra and X-ray crystallographic analyses of the rotaxanes showed that the crown ether component was captured on the ammonium group in ammonium-type rotaxane by strong hydrogen-bonding intercomponent interaction. The conformation around the ammonium group was fixed by the hydrogen-bonding interaction. Meanwhile, the conformation of the amide-type rotaxane was determined by the weak CH/π interaction between the methylene group in crown ether and the benzene ring of the axle component. The N-acylation of ammonium-type rotaxane is useful for the preparation of both functionalized rotaxanes and weak intercomponent interaction-based rotaxanes.
