2380-84-9Relevant articles and documents
Palladium-Catalyzed Silacyclization of (Hetero)Arenes with a Tetrasilane Reagent through Twofold C?H Activation
Wang, Dingyi,Li, Mingjie,Chen, Xiangyang,Wang, Minyan,Liang, Yong,Zhao, Yue,Houk, Kendall N.,Shi, Zhuangzhi
, p. 7066 - 7071 (2021)
The use of an operationally convenient and stable silicon reagent (octamethyl-1,4-dioxacyclohexasilane, ODCS) for the selective silacyclization of (hetero)arenes via twofold C?H activation is reported. This method is compatible with N-containing heteroarenes such as indoles and carbazoles of varying complexity. The ODCS reagent can also be utilized for silacyclization of other types of substrates, including tertiary phosphines and aryl halides. A series of mechanistic experiments and density functional theory (DFT) calculations were used to investigate the preferred pathway for this twofold C?H activation process.
Cu(I)-Catalyzed Site Selective Acyloxylation of Indoline Using O2 as the Sole Oxidant
Ahmad, Ashfaq,Dutta, Himangsu Sekhar,Khan, Bhuttu,Kant, Ruchir,Koley, Dipankar
, p. 1644 - 1649 (2018)
A Cu(I)-catalyzed regioselective cross-dehydrogenative coupling of indoline with a variety aryl and alkyl carboxylic acids is described. The divergent process for the oxygenation was achieved in satisfactory yields under additive free conditions, which provides an efficient strategy for the regioselective C7 functionalization of indolines using inexpensive copper catalyst. Oxygen as the sole oxidant is required in this protocol. The method is tolerated by a wide range of functional groups. Preliminary mechanistic study provided support for a reversible C?H bond metallation step. (Figure presented.).
Acyl-Directed ortho-Borylation of Anilines and C7 Borylation of Indoles using just BBr3
Iqbal, Saqib A.,Cid, Jessica,Procter, Richard J.,Uzelac, Marina,Yuan, Kang,Ingleson, Michael J.
, p. 15381 - 15385 (2019/10/22)
Indoles are privileged heterocycles found in many biologically active pharmaceuticals and natural products. However, the selective functionalization of the benzenoid moiety in indoles in preference to the more reactive pyrrolic unit is a significant challenge. Herein we report that N-acyl directing groups enable the C7-selective C?H borylation of indoles using just BBr3. This transformation shows some functional-group tolerance and notably proceeds with C6 substituted indoles. The directing group can be readily removed in situ and the products isolated as the pinacol boronate esters. Acyl-directed electrophilic borylation can be extended to carbazoles and anilines with excellent ortho selectivity. 4-amino-indoles are amenable to this process, with acyl group installation and directed electrophilic C?H borylation enabling selective formation of C5-BPin-indoles.