77435-14-4Relevant academic research and scientific papers
Rapid access to 3-acyl indoles using ethyl acetate/triflic acid couple as the acylium donor and Cu(OAc)2catalysed aerial oxidation of indole benzoins
Talukdar, Ranadeep
supporting information, p. 8876 - 8880 (2020/11/23)
Esters are potential acyl donors but are relatively unexplored for that purpose. A facile installation of acyl groups at the C-3 position of indoles under triflic acid catalysed conditions with easily available and cheap esters as new acylating agents is described herein. Furthermore, heterocycles like N-protected pyrrole, furan and thiophene were also suitable substrates for similar C-2 acylation. Analogous C-3 benzoylated products of indole were obtained, albeit in lower yields, by using methyl benzoate as a benzoyl donor. The benzoylated products were synthesised in much better yields via a copper(ii) catalysed aerial oxidation of indole containing benzoins. This journal is
Weak Coordination Enabled Switchable C4-Alkenylation and Alkylation of Indoles with Allyl Alcohols
Banerjee, Sonbidya,De, Pinaki Bhusan,Mishra, Manmath,Pradhan, Sourav,Punniyamurthy, Tharmalingam
supporting information, (2020/03/11)
A weak carbonyl coordination facilitated tunable reactivity between alkenylation and alkylation of indoles at the C4 C-H site is presented using readily accessible allylic alcohols in the presence of Rh catalysis by switching the additives or directing group. Exclusive site selectivity, functional group tolerance, and late-stage modifications are the important practical features.
Weak Coordination-Guided Regioselective Direct Redox-Neutral C4 Allylation of Indoles with Morita-Baylis-Hillman Adducts
Pradhan, Sourav,De, Pinaki Bhusan,Punniyamurthy, Tharmalingam
supporting information, p. 9898 - 9903 (2019/12/24)
A weak carbonyl coordination-guided regioselective C4 allylation of indoles is demonstrated using the versatile Morita-Baylis-Hillman adduct in the presence of Rh catalysts in a redox-neutral fashion. The substrate scope, functional group diversity, oxidant free character, mechanistic aspects, and synthetic utilities are important practical features.
Regiocontrolled direct C4 and C2-methyl thiolation of indoles under rhodium-catalyzed mild conditions
Maity, Saurabh,Karmakar, Ujjwal,Samanta, Rajarshi
supporting information, p. 12197 - 12200 (2017/11/16)
A straightforward Rh(iii)-catalyzed general strategy was developed for the site-selective remote C4 (sp2) and C2 (sp3)-methyl thiolation of an indole core, keeping the oxime directing group at the C3 position. The transformation was accomplished under mild conditions with a wide scope and functional group tolerance. The directing group can easily be removed after operation. Methyl substitution at the C2 position of the indole core led to C2 (sp3)-methyl thiolation.
Pd-catalyzed cascade reactions between: O -iodo- N -alkenylanilines and tosylhydrazones: Novel approaches to the synthesis of polysubstituted indoles and 1,4-dihydroquinolines
Paraja, Miguel,Valdés, Carlos
supporting information, p. 6312 - 6315 (2016/05/19)
Two different Pd-catalyzed cascade reactions between o-iodo-N-alkenylanilines and tosylhydrazones are described. The outcome of the cascade processes is determined by the substitution on the N-alkenyl fragment. The reactions with N-tosyl-N-ethylene-o-iodoanilines lead to indoles through a sequence that involves the sequential migratory insertions of a carbene ligand and a C-C double bond, featuring a 5-exo-trig cyclization. The reactions with N-alkyl-N-alkenyl-o-iodoanilines provide 1,4-dihydroquinolines through a cascade reaction that includes a formal 6-endo-trig cyclization. In both cases the benzofused heterocycles are built through the formation of two C-C bonds on the hydrazonic carbon atom.
Synthesis of carbazolones and 3-acetylindoles via oxidative C-N bond formation through PIFA-mediated annulation of 2-aryl enaminones
Ban, Xu,Pan, Yan,Lin, Yingfu,Wang, Songqing,Du, Yunfei,Zhao, Kang
, p. 3606 - 3609 (2012/06/01)
A series of carbazolone derivatives and 3-acetylindoles have been achieved via PIFA-mediated intramolecular cyclization of 2-aryl enaminones. This process allows the N-moiety on the side-chain to be annulated to the benzene ring via the metal-free oxidative aromatic C-N bond formation.
Fischer Indole Synthesis of 3-Acyl and 3-Alkoxy-carbonylindoles
Mills, Keith,Khawaja, Ibtisam K. Al,Al-Saleh, Fowzia,Joule, John A.
, p. 636 - 641 (2007/10/02)
N-Benzyl-N-phenylhydrazine derivatives of 1,3-diketones and 1,3-ketoesters undergo normal Fischer cyclisations to indoles, but no method could be found for the subsequent removal of the N-protecting group.No method could be found for the indolisation of N-aroyl-N-phenylhydrazine derivatives of dimedone with retention of the N-protecting group, though heating in tetralin did effect the electrocyclic step of the Fischer sequence and the formation of a carbon-carbon bond.
