156901-91-6Relevant academic research and scientific papers
Efficient palladium catalysts containing original imidazolium-tagged chiral diamidophosphite ligands for asymmetric allylic substitutions in neat ionic liquid
Bravo, Maritza J.,Favier, Isabelle,Saffon, Nathalie,Ceder, Rosa M.,Muller, Guillermo,Gomez, Montserrat,Rocamora, Merce
, p. 771 - 779 (2014/03/21)
New imidazolium-tagged chiral diamidophosphite ligands, (S,S)-a and (R)-b, derived from (S,S)-N,N′-dibenzyl-1,2-cyclohexanediamine and (R)-N,N′-dimethyl-1,1′-binaphthyl-2,2′-diamine, respectively, and the corresponding palladium allylic complexes of general formula [PdCl(η3-2-Me-C3H4)(κ1P-L) ]BF4 (1a,b) and [Pd(η3-2-Me-C3H 4)(κ1P-L)2](BF4)3 (2a,b) were synthesized and fully characterized, including the X-ray crystal structure for 1b. These original Pd/L catalytic systems were applied in asymmetric allylic alkylation, amination, and sulfonylation using rac-3-acetoxy-1,3-diphenyl-1-propene as a substrate in neat ionic liquids, [bmim][PF6] and [Pyr][NTf2]. The best results in terms of enantioselectivity were obtained with the catalytic precursor 1b in [Pyr][NTf2]. The catalytic phase containing 1b for the allylic amination could be recycled up to six times without significant loss of asymmetric induction.
Diamidophosphites with isomeric carborane fragments: a comparison of catalytic activity in asymmetric Pd-catalyzed allylic substitution reactions
Lyubimov, Sergey E.,Davankov, Vadim A.,Gavrilov, Konstantin N.,Grishina, Tatiana B.,Rastorguev, Eugenie A.,Tyutyunov, Andrey A.,Verbitskaya, Tatiana A.,Kalinin, Valery N.,Hey-Hawkins, Evamarie
scheme or table, p. 1682 - 1684 (2010/06/13)
New chiral diamidophosphite ligands containing electron-donating 9-meta-carborane and electron-withdrawing 1-meta-carborane substituents have been synthesized. The ligand 3a with an electron-donating group demonstrated high enantioselectivity in Pd-cataly
Palladium catalyzed asymmetric sulfonylation mediated chiral β-hydroxy- and β-(o-diphenylphosphino)benzoyloxy (o-diphenyl phosphino)benzamides
Wolfe, Jesse A.,Hitchcock, Shawn R.
scheme or table, p. 2690 - 2695 (2011/03/17)
The palladium catalyzed asymmetric allylic sulfonylation reaction has been investigated employing β-hydroxy- and β-(o-diphenylphosphino) benzoyloxy (o-diphenyl phosphino)benzamides as chiral, non-racemic ligands. The bisphosphine β-benzoyloxybenzamide ligands proved to be the best ligands for this process. Competitive transition states for the (1S,2R)-norephedrine derived ligand 14 are compared and a rationale is provided for the observed enantioselectivities.
