113060-95-0Relevant academic research and scientific papers
Direct synthesis of pyrazoles from esters using tert-butoxide-assisted C-(C=O) coupling
Kim, Bo Ram,Sung, Gi Hyeon,Ryu, Ki Eun,Lee, Sang-Gyeong,Yoon, Hyo Jae,Shin, Dong-Soo,Yoon, Yong-Jin
supporting information, p. 9201 - 9204 (2015/06/08)
This paper describes the direct synthesis of pyrazoles from esters that comprises two sequential reactions: tert-butoxide-assisted C-C(=O) coupling reaction to yield β-ketonitrile or α,β-alkynone intermediates, and condensation by hydrazine addition. The method reported allows for easy control of the regioselectivity and structure of substituents at N-1, C-3, C-4 and/or C-5 positions.
Iridium-catalyzed addition of aroyl chlorides and aliphatic acid chlorides to terminal alkynes
Iwai, Tomohiro,Fujihara, Tetsuaki,Terao, Jun,Tsuji, Yasushi
, p. 1268 - 1274 (2012/03/12)
Iridium complexes show high catalytic activity in intermolecular additions of acid chlorides to terminal alkynes to afford valuable (Z)-β-chloro- α,β-unsaturated ketones. Ligands in the catalytic system play a crucial role in this reaction. An N-heterocyclic carbene (NHC) is an efficient ligand for the addition of aroyl chlorides, while dicyclohexyl(2-methylphenyl) phosphine (PCy2(o-Tol)) is indispensable for the reaction of aliphatic acid chlorides. The addition reactions proceed regio- and stereoselectively with suppression of decarbonylation and β-hydrogen elimination, which have been two major intrinsic problems in transition-metal-catalyzed reactions. Stoichiometric reactions of active iridium catalysts with aroyl chlorides and aliphatic acid chlorides are carried out to gain insights into the reaction mechanisms.
