293744-64-6Relevant academic research and scientific papers
Highly regioselective, electrophile induced cyclizations of 2-(prop-1-ynyl)benzamides
Chinta, Bhavani Shankar,Sanapa, Harikrishna,Vasikarla, Kamala Prasad,Baire, Beeraiah
, p. 3947 - 3951 (2018)
We report an electrophile promoted, highly regioselective (～100%) synthesis of 5-membered haloimidiates from 2-(1-alkynyl)benzamides under metal free conditions. The steric bulk in association with neighbouring group assistance at the propargylic carbon of an alkyne has been employed as the dictating factor to achieve the regioselectivity. A very broad structural diversity has been observed for propargylic alcohols and acetates, and for amide functional groups. Control experiments supported the role of the steric bulk as well as neighbouring group assistance from the oxygen atom of the substituent for the observed high regioselectivity.
Divergent palladium iodide catalyzed multicomponent carbonylative approaches to functionalized isoindolinone and isobenzofuranimine derivatives
Mancuso, Raffaella,Ziccarelli, Ida,Armentano, Donatella,Marino, Nadia,Giofrè, Salvatore V.,Gabriele, Bartolo
, p. 3506 - 3518 (2014/05/06)
2-Alkynylbenzamides underwent different reaction pathways when allowed to react under PdI2-catalyzed oxidative carbonylation conditions, depending on the nature of the external nucleophile and reaction conditions. Thus, oxidative carbonylation of 2-ethynylbenzamides, bearing a terminal triple bond, carried out in the presence of a secondary amine as external nucleophile, selectively led to the formation of 3-[(dialkylcarbamoyl)methylene]isoindolin-1- ones through the intermediate formation of the corresponding 2-ynamide derivatives followed by intramolecular nucleophilic attack by the nitrogen of the benzamide moiety on the conjugated triple bond. On the other hand, 3-[(alkoxycarbonyl)methylene]isobenzofuran-1(3H)imines were selectively obtained when the oxidative carbonylation of 2-alkynylbenzamides, bearing a terminal or an internal triple bond, was carried out in the presence of an alcohol R′OH (such as methanol or ethanol) as the external nucleophile and HC(OR′)3 as a dehydrating agent, necessary to avoid substrate hydrolysis. In this latter case, the reaction pathway leading to the isobenzofuranimine corresponded to the 5-exo-dig intramolecular nucleophilic attack of the oxygen of the benzamide moiety on the triple bond coordinated to the metal center followed by alkoxycarbonylation. The structures of representative products have been confirmed by X-ray crystallographic analysis.
Product selectivity control in the heteroannulation of o-(1-Alkynyl)benzamides
Bianchi, Gabriele,Chiarini, Marco,Marinelli, Fabio,Rossi, Leucio,Arcadi, Antonio
scheme or table, p. 136 - 142 (2010/06/20)
The selective synthesis of (Z)- or (E)-3-aryl/vinyl/alkylidene-isoindolones, and 2-benzopyran derivatives from o-(1-alkynyl)benzamides by means of a suitable choice of bases or silver catalysis is described.
Palladium-catalysed heteroannulation with terminal alkynes: A highly regio- and stereoselective synthesis of (Z)-3-aryl(alkyl)idene isoindolin-1- ones
Kundu, Nitya G.,Khan, M. Wahab
, p. 4777 - 4792 (2007/10/03)
A highly regio- and stereoselective method for the synthesis of (Z)-3- aryl(alkyl)idene isoindolin-1-ones through palladium-copper catalysis is described. 2-Iodobenzamide 1 and its substituted derivatives 2-10 were reacted with terminal alkynes 11-19 in the presence of (PPh3)2PdCl2, CuI, and Et3N in DMF mostly at 80°C for 16 h to yield the 2-alkynyl substituted benzamides 20-38, 40-45, 77 which could then be cyclised with NaOEt in EtOH to the 3-aryl(alkyl)idene isoindolin-1-ones 46-49, 51, 53-55, 57, 59-71, 73 and 75. In certain cases, the isoindolin-1-ones 50, 52, 56 and 58 could be directly obtained by the palladium-catalysed reactions. (C) 2000 Elsevier Science Ltd.
A highly regio and stereoselective synthesis of (Z)-3- aryl(alkyl)idene isoindolin-1-ones via palladium catalyzed annulation of terminal alkynes
Khan, M. Wahab,Kundu, Nitya G.
, p. 1435 - 1437 (2007/10/03)
o-Iodobenzamide or its N-substituted derivatives 4-10 and terminal alkynes 11-17 reacted in DMF in the presence of bis(triphenylphosphine)palladium(II)chloride, cuprous iodide and triethylamine leading to (Z)-3- arylidene isoindolin-1-ones (22, 24, 27 and 28) or o-alkynyl N-substituted benzamides (I). The latter could be cyclised with sodium in ethanol in a completely regio and stereoselective manner to (Z)-3-aryl(alkyl)idene isoindolin-1-ones 18-35.
