148564-88-9Relevant articles and documents
3-(o-Trifluoroacetamidoaryl)-1-propargylic esters: common intermediates for the palladium-catalyzed synthesis of 2-aminomethyl-, 2-vinylic, and 2-alkylindoles
Ambrogio, Ilaria,Cacchi, Sandro,Fabrizi, Giancarlo,Prastaro, Alessandro
experimental part, p. 8916 - 8929 (2009/12/07)
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 ethyl 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. Ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates bearing an alkyl substituent at the propargylic carbon and ethyl 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, ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates afford 2-alkylindoles in good to excellent yields.
Palladium-catalyzed heteroannulation with acetylenic carbinols as synthons-synthesis of quinolines and 2,3-dihydro-4(1H)-quinolones
Mahanty, Jyan S.,De, Mahuya,Das, Palas,Kundu, Nitya G.
, p. 13397 - 13418 (2007/10/03)
o-Iodoanilides 4 reacted with terminal acetylenic carbinols 5 under palladium-catalyzed conditions to yield o-substituted anilides 6. Most of the anilides 6 could be cyclized with NaOEt/EtOH to 2-arylquinolines 2. o-Iodoanilines 7 reacted with carbinols 5 leading to 8 which on palladium(II) assisted cyclisation afforded substituted quinolines 2. An excellent synthesis of the alkaloid dubamine (2n) is reported. Also, the anilides 6 on acid-catalyzed rearrangement, deprotection and cyclisation led to the 2-aryl-2, 3-dihydro-4(1H)-quinolones 16.