486406-54-6Relevant academic research and scientific papers
Rhodium-Catalyzed Annulation of Phenacyl Ammonium Salts with Propargylic Alcohols via a Sequential Dual C-H and a C-C Bond Activation: Modular Entry to Diverse Isochromenones
Nanubolu, Jagadeesh Babu,Reddy Singam, Maneesh Kumar,Sridhar Reddy, Maddi,Suresh, Vavilapalli,Suri Babu, Undamatla
supporting information, p. 7888 - 7893 (2021/10/25)
Given their omnipresence in natural products and pharmaceuticals, isochromenone congeners are one of the most privileged scaffolds to synthetic chemists. Disclosed herein is a dual (ortho/meta) C-H and C-C activation of phenacyl ammonium salts (acylammonium as traceless directing group) toward annulation with propargylic alcohols to accomplish rapid access for novel isochromenones by means of rhodium catalysis from readily available starting materials. This operationally simple protocol features broad substrate scope and wide functional group tolerance. Importantly, the protocol circumvents the need of any stoichiometric metal oxidants and proceeds under aerobic conditions.
Sonogashira-Hagihara and Buchwald-Hartwig cross-coupling reactions with sydnone and sydnone imine derived catalysts
Lücke, Ana-Luiza,Pruschinski, Lucas,Freese, Tyll,Schmidt, Andreas
supporting information, p. 94 - 104 (2020/08/26)
Seven different palladium complexes of sydnones and sydnone imines and a co-catalyst system consisting of lithium sydnone-4-carboxylate and Pd(PPh3)4 catalyzed Sonogashira-Hagihara reactions between (hetero)- aromatic bromides and 2-methylbut-3-yn-2-ol (52 examples, up to 100% yield). The co-catalyst system and a sydnone Pd complex were also tested in Buchwald-Hartwig reactions (9 examples, up to 100% yield). (Equation Presented).
Palladium-catalyzed oxidative deacetonative coupling of 4-aryl-2-methyl-3-butyn-2-ols with H-phosphonates
Li, Xiang,Sun, Suyan,Yang, Fan,Kang, Jianxun,Wu, Yusheng,Wu, Yangjie
, p. 2432 - 2436 (2015/03/04)
An efficient and generally applicable protocol for palladium-catalyzed oxidative deacetonative coupling of 4-aryl-2-methyl-3-butyn-2-ols with dialkyl H-phosphonates has been developed. This methodology provides a new and practical route to alkynylphosphonates using the inexpensive 4-aryl-2-methyl-3-butyn-2-ols as the alkyne sources. This reaction could also be performed with aryl bromides, 2-methyl-3-butyne-2-ol and dialkyl H-phosphonates using the cheap 2-methyl-3-butyne-2-ol as an alkyne source. This journal is
K3PO4-KOH mixture as efficient reagent for the deprotection of 4-aryl-2-methyl-3-butyn-2-ols to terminal acetylenes
Smeyanov, Alexey,Schmidt, Andreas
supporting information, p. 2809 - 2816 (2013/08/23)
A mixture of potassium hydroxide and potassium phosphate was found to be an active reagent mixture for the cleavage of 2-hydroxypropyl-protected acetylenes. The reaction was performed in toluene at reflux temperature and gave terminal acetylenes in good to excellent yields within very short periods of time. Numerous other functional groups are tolerated. Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications for full experimental and spectral details.
Enantiospecific and regioselective opening of 2-alkyl nosylaziridines by indoles mediated by boron trifluoride. Application to a practical synthesis of a GnRH antagonist
Farr, Roger N.,Alabaster, Ramon J.,Chung, John Y.L.,Craig, Bridgette,Edwards, John S.,Gibson, Andrew W.,Ho, Guo-Jie,Humphrey, Guy R.,Johnson, Simon A.,Grabowski
, p. 3503 - 3515 (2007/10/03)
An efficient, high yield process for the synthesis of a GnRH antagonist has been developed. We have demonstrated that under boron trifluoride mediation, nosyl aziridines will react with 2-arylindole derivatives to afford β-substituted tryptamines in an enantiospecific process with remarkably high regioselectivity. The scope of the reaction was explored with several 2-substituted nosyl aziridines. The key reaction was developed expressly for the GnRH antagonist program and has been demonstrated on 40 kilogram scale.
