Ambrogio, Ilaria published the artcile3-(o-Trifluoroacetamidoaryl)-1-propargylic esters: common intermediates for the palladium-catalyzed synthesis of 2-aminomethyl-, 2-vinylic, and 2-alkylindoles, SDS of cas: 57663-18-0, the publication is Tetrahedron (2009), 65(44), 8916-8929, database is CAplus.
3-(O-Trifluoroacetamidoaryl)-1-propargylic esters have been used as common synthetic intermediates for the preparation of a variety of 3-unsubstituted 2-substituted indoles. Treating Et 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates unsubstituted or containing an aryl substituent at the propargylic carbon with piperazines and Pd(PPh3)4 in THF at 80 °C affords 2-(piperazin-1-ylmethyl)indoles in excellent yields. Good to excellent yields of 2-aminomethylindoles are also obtained with other secondary amines. Et 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates bearing an alkyl substituent at the propargylic carbon and Et 3-(o-trifluoroacetamidoaryl)-1-propargylic acetates disubstituted at the propargylic carbon give 2-vinylic indoles with the Pd(OAc)2/PPh3 combination and Et3N in THF at 80 °C. Formation of 2-vinylic indoles is quite stereoselective, generating trans vinylic derivatives, at least with the substrates that we have investigated. In the presence of formic acid, Et3N, and Pd(PPh3)4 in MeCN at 80 °C, Et 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates afford 2-alkylindoles in good to excellent yields.
Tetrahedron published new progress about 57663-18-0. 57663-18-0 belongs to indole-building-block, auxiliary class Indole,Ester, name is Methyl 2-methyl-1H-indole-5-carboxylate, and the molecular formula is C11H11NO2, SDS of cas: 57663-18-0.
Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles