42790-42-1Relevant articles and documents
Synthesis of N-alkyl-N′-aryl or Alkenylpiperazines: A Copper-Catalyzed C–N Cross-Coupling in the Presence of Aryl and Alkenyl Triflates and DABCO
Ghazanfarpour-Darjani, Majid,Barat-Seftejani, Forugh,Khalaj, Mehdi,Mousavi-Safavi, Seyed Mahmoud
, (2017/08/18)
Unsymmetrical piperazines are key constituents of many pharmaceuticals. Given that the selective introduction of an aryl and alkyl motif onto the piperazine is not always straightforward, direct arylation and alkenylation of 1,4-diaza-bicyclo[2.2.2]octane would obviate the inefficiencies associated with the preparation of these target molecules. We have utilized alkyl halides, aryl or alkenyl triflates, and 1,4-diaza-bicyclo[2.2.2]octane for the synthesis of N-alkyl-N′-aryl or alkenylpiperazines. The optimum conditions are developed using CuCl, t-BuOLi in NMP. Alkenyl triflates requires N,N′-dimethylethylenediamine and higher temperature to afford the desired cross-coupled product. Substrates bearing electron-deficient and electron-rich groups were successfully coupled under the optimum reaction conditions.
Radiosynthesis and evaluation of [18F]Selectfluor bis(triflate)
Teare, Harriet,Robins, Edward G.,Kirjavainen, Anna,Forsback, Sarita,Sandford, Graham,Solin, Olof,Luthra, Sajinder K.,Gouverneur, Veronique
supporting information; experimental part, p. 6821 - 6824 (2010/12/25)
(Figure Presented) Selectfluor, one of the most reactive and commonly used electrophilic fluorinating N-F reagents, has been radiolabeled with 18F. The resulting new [18F]-labeled N-F reagent is safe, nontoxic, and easy to handle. The combined use of [18F]Selectfluor bis(triflate) and AgOTf allows for the preparation of electron-rich 18F-aromatic compounds through a simple "shake and mix" protocol at room temperature (see scheme; SA=specific activtiy).
Dealkylation of Quaternary Ammonium Salts by Thiolate Anions: A Model of the Cobalamin-independent Methionine Synthase Reaction.
Hilhorst, Ellen,Chen, Tjoe B. R. A.,Iskander, Atef S.,Pandit, Upendra K.
, p. 7837 - 7848 (2007/10/02)
The reactions of thiolate ions derived from thiophenol and homocysteine with substituted quaternary ammonium salts result in alkyl transfer from nitrogen to sulfur.A radical mechanism for this transalkylation, accounts for the reactivity pattern of the substrate salts.In a model study of the cobalamin-independent methionine synthase reaction, 5,5,6,7-tetramethyl-5,6,7,8-tetrahydropteridinium salt (25), which can be considered as a model for the natural coenzyme 5-CH3H4-folate (1), was allowed to react with the thiolate of homocysteine, whereupon the formation of methionine was observed in good yield.These results suggest that in the enzymatic process the N(5)-CH3 bond may be activated for the methyl transfer step, by coordination of the N(5) with an electrophile or a proton at the active site.