111448-45-4Relevant articles and documents
Preparation of Functionalized Diaryl- and Diheteroaryllanthanum Reagents by Fast Halogen–Lanthanum Exchange
Benischke, Andreas D.,Anthore-Dalion, Lucile,Berionni, Guillaume,Knochel, Paul
supporting information, p. 16390 - 16394 (2017/11/28)
Aryl and heteroaryl halides (X=Br, I) undergo a fast and convenient halogen–lanthanum exchange with nBu2LaMe, which leads to functionalized diaryl- and diheteroaryllanthanum derivatives. Subsequent trapping reactions with selected electrophiles, such as ketones, aldehydes, or amides, proceeded smoothly at ?50 °C in THF, affording polyfunctionalized alcohols and carbonyl derivatives. Kinetic competition experiments revealed a similar reactivity trend as for Br/Mg exchange, but 106-times higher rates, making it comparable to Br/Li exchange.
Rapid access to halohydrofurans via bronsted acid-catalyzed hydroxylation/halocyclization of cyclopropyl methanols with water and electrophilic halides
Mothe, Srinivasa Reddy,Kothandaraman, Prasath,Rao, Weidong,Chan, Philip Wai Hong
experimental part, p. 2521 - 2531 (2011/05/14)
A one-pot, two-step method to prepare 3-halohydrofurans efficiently by TfOH-catalyzed hydroxylation/halocyclization of cyclopropyl methanols with H2O and N-halosuccinimide (NXS, X=1, Br, Cl) or Selectfluor is described. The reactions proceed rapidly under mild and operationally straightforward conditions with a catalyst loading as low as 1 mol % and afford the 3-halohydrofuran products in moderate to excellent yields and, in most cases, with preferential cis diastereoselectivity. The method was shown to be applicable to cyclopropyl methanols containing electron-withdrawing, electron-donating, and sterically demanding functional groups and electrophilic halide sources. The mechanism is suggested to involve protonation of the alcohol substrate by the Bronsted acid catalyst and ionization of the starting material. This results in ring-opening of the cyclopropane moiety and in situ formation of a homoallylic alcohol intermediate, which undergoes subsequent intramolecular halocyclization on treating with the electrophilic halide source to give the halohydrofuran. The observed cis product selectivity is thought to be determined by the reaction proceeding through an in situ generated unsaturated alcohol intermediate that contains a (Z)-alkene moiety under the kinetically controlled conditions.
Diarylalkyl-substituted alkylamines and medicaments containing them
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, (2008/06/13)
A compound I STR1 in which R1 is cycloalkyl, alkenyl, cycloalkenyl, phenyl, STR2 where J, L, M, and E are methine or nitrogen and J', L', M', and E' are methylene, carbonyl or imino; R2 is phenyl or phenylalkyl; a is various amine ra