1416955-79-7Relevant articles and documents
Lithium–Bromide Exchange versus Nucleophilic Addition of Schiff's base: Unprecedented Tandem Cyclisation Pathways
Orr, Samantha A.,Border, Emily C.,Andrews, Philip C.,Blair, Victoria L.
supporting information, (2019/08/16)
By exploring lithium–bromide exchange reactivity of aromatic Schiff's bases with tert-butyllithium (tBuLi), we have revealed unprecedented competitive intermolecular and intramolecular cascade annulation pathways, leading to valuable compounds, such as iso-indolinones and N-substituted anthracene derivatives. A series of reaction parameters were probed, including solvent, stoichiometry, sterics and organolithium reagent choice, in order to understand the influences that limit such ring-closing pathways. With two viable reactivity options for the organolithium on the imine; namely, nucleophilic addition or lithium–bromide exchange, a surprising competitive nature was observed, where nucleophilic addition dominated, even under cryogenic conditions. Considering the most commonly used solvents for lithium–bromide exchange, tetrahydrofuran (THF) and diethyl ether (Et2O), contrasting reactivity outcomes were revealed with nucleophilic addition promoted in THF, while Et2O yielded almost double the conversion of cyclic products than in THF.
An efficient, rapid and solvent-free synthesis of branched imines using sulfated anatase-titania as a novel solid acid catalyst
Kumar,Krishnakumar,Sobral, Abiiio J. F. N.,Subash,Swaminathan,Sankaran
, p. 1231 - 1238 (2017/04/28)
An eco-friendly solid acid catalyst sulfated anatase-titania (TiO2-SO42-) has been used for the synthesis of branched imine derivatives from 2,6-di(propan-2-yl)aniline with different substituted aromatic aldehydes by simpl
Organoantimony(iii) compounds containing (imino)aryl ligands of the type 2-(RNCH)C6H4 (R = 2′,4′,6′-Me 3C6H2, 2′,6′-iPr 2C6H3): Bromides and chalcogenides
Preda, Ana Maria,Rat, Ciprian I.,Silvestru, Cristian,Breunig, Hans J.,Lang, Heinrich,Rueffer, Tobias,Mehring, Michael
, p. 1144 - 1158 (2013/02/23)
The reaction of 2-(RNCH)C6H4MgBr [R = 2′,4′,6′-Me3C6H2 (R 1), 2′,6′-iPr2C6H 3 (R2)] [prepared from 2-(R1NCH)C 6H4Br (1) or 2-(R2NCH)C6H 4Br (2) and Mg] with SbCl3 in a 2:1 and 1:1 molar ratio followed by treatment with an aqueous KBr solution gave [2-(R 1NCH)C6H4]2SbBr (3) and [2-(R 2NCH)C6H4]2SbBr (4) as well as [2-(R1NCH)C6H4]SbBr2 (6) and [2-(R2NCH)C6H4]SbBr2 (7). Treatment of 4 with Na2S·9H2O provided the dinuclear [{2-(R2NCH)C6H4}2Sb]2S (5). Heterocyclic species, i.e. the oxide cyclo-[{2-(R2NCH)C 6H4}SbO]3 (8) and the sulfides cyclo-[{2-(R1NCH)C6H4}SbS]2 (9) and cyclo-[{2-(R2NCH)C6H4}SbS]2 (10), were obtained by reacting dibromides 6 and 7 with KOH and Na 2S·9H2O, respectively, in a water-toluene solvent mixture. The sulfide 10 reacted with [W(CO)5(thf)] to yield the heterometallic complex cyclo-[{2-(R2NCH)C6H 4}SbS]2[W(CO)5] (11). The compounds were characterised by multinuclear NMR spectroscopy in solution, mass spectrometry and IR spectroscopy in the solid state. The molecular structures of 4, 5, 6·CHCl3, 7, 9·CH2Cl2, 10 and 11·0.25CH3OH were established by single-crystal X-ray diffraction. Theoretical calculations using DFT methods were carried out on bromide 7 and the geometrical isomers of its dimer association as well as the geometrical isomers of sulfide 10 and its monomer. The Royal Society of Chemistry 2013.
