Search results for "Phosphinite"
showing 9 items of 9 documents
Modular P-Chirogenic Phosphine-Sulfide Ligands: Clear Evidence for Both Electronic Effect and P-Chirality Driving Enantioselectivity in Palladium-Cat…
2015
Using the ephedrine methodology, modular stereoselective syntheses of a new class of P-chirogenic phosphines bearing a sulfur-chelating arm (P*,S-hybrid ligand) are described. A first series of syntheses based on a Fries-like rearrangement of P-chirogenic phosphinite-boranes, which are prepared from 2-bromobenzyl or 2-bromophenethyl alcohol and are mediated by metal–halide exchange, have been performed. This rearrangement affords phosphine-boranes stereospecifically with an o-hydroxyalkylphenyl substituent. The latter residue is subsequently converted into a sulfur-containing group. In a second series, the stereoselective syntheses were achieved according to a new strategy involving a react…
Design of P-Chirogenic Aminophosphine-Phosphinite Ligands at Both Phosphorus Centers: Origin of Enantioselectivities in Pd-Catalyzed Allylic Reaction…
2020
International audience; We have recently patented an unprecedented stereospecific N→O phosphinyl migration process which transforms P-chirogenic aminophosphines into phosphinites. A fine design of aminophosphine phosphinite ligands (AMPP*) derived from ephedrine and bearing a P-chirogenic center either at the aminophosphine or phosphinite moiety, was performed. The synthesis of AMPP* ligands with P-chirogenic aminophosphine moiety was based on the well-established stereospecific reaction of oxazaphospholidine-borane with organolithium reagents, followed by trapping with a chlorophosphine and borane decomplexation. Concurrently, the preparation of AMPP* ligands with P-chirogenic phosphinite …
Enantioselective Hydrogenation Catalysis Aided by a σ-Bonded Calix[4]arene to a P-Chirogenic Aminophosphane Phosphinite Rhodium Complex
2010
The first P-chirogenic aminophosphane−phosphinite (AMP*P) ligand (4a) supported on the upper rim of a calix[4]arene moiety was synthesized in two steps using the ephedrine methodology. Ligand 4a wa...
CCDC 619378: Experimental Crystal Structure Determination
2007
Related Article: C.Darcel, D.Moulin, J.-C.Henry, M.Lagrelette, P.Richard, P.D.Harvey, S.Juge|2007|Eur.J.Org.Chem.|2007|2078|doi:10.1002/ejoc.200600966
CCDC 1982654: Experimental Crystal Structure Determination
2023
Related Article: Antonin Jaillet, Christophe Darcel, Jérôme Bayardon, Adrien Schlachter, Christine Salomon, Yoann Rousselin, Pierre Harvey, Sylvain Jugé|2020|J.Org.Chem.|85|14391|doi:10.1021/acs.joc.0c00536
CCDC 1982650: Experimental Crystal Structure Determination
2023
Related Article: Antonin Jaillet, Christophe Darcel, Jérôme Bayardon, Adrien Schlachter, Christine Salomon, Yoann Rousselin, Pierre Harvey, Sylvain Jugé|2020|J.Org.Chem.|85|14391|doi:10.1021/acs.joc.0c00536
CCDC 1982651: Experimental Crystal Structure Determination
2023
Related Article: Antonin Jaillet, Christophe Darcel, Jérôme Bayardon, Adrien Schlachter, Christine Salomon, Yoann Rousselin, Pierre Harvey, Sylvain Jugé|2020|J.Org.Chem.|85|14391|doi:10.1021/acs.joc.0c00536
Modular P-Chirogenic Aminophosphane-Phosphinite Ligands for Rh-Catalyzed Asymmetric Hydrogenation: A New Model for Prediction of Enantioselectivity
2007
An original series of P-chirogenic aminophosphane-phosphinite (AMPP) ligands has been synthesized from (+)- or(–)-ephedrine in 23 to 61 % overall yields by a versatile three-step methodology. The AMPP ligands, bearing either one or two P-chirogenic centers, were used in the form of rhodium complexes for the catalyzed hydrogenation of α-acetamidocinnamate as a test reaction. Notably, even with AMPP ligands all derived from (+)-ephedrine, variation of the substituent on a P-center allowed the phenylalanine derivatives to be obtained in either (S) or (R) absolute configurations, with ee values ranging from 99 % (S) to 88 % (R). The asymmetric induction was analyzed with the aid of X-ray struct…
[60]Fullerene l -Amino Acids and Peptides: Synthesis under Phase-Transfer Catalysis Using a Phosphine–Borane Linker. Electrochemical Behavior
2017
International audience; A new method to link amino acid and peptide derivatives to [60]fullerene is described. It uses hydrophosphination with a secondary phosphine borane. First, the stereoselective synthesis of secondary phosphine borane amino acid derivatives was achieved by alkylation of phenylphosphine borane with gamma-iodo-alpha-amino ester reagents under phase transfer catalysis (PTC). Second, a sec-phosphine borane amino ester was saponified and coupled with alpha,gamma-diamino esters to afford the corresponding dipeptide derivatives in good yields. Finally, the hydrophosphination reaction of [60]fullerene by the sec-phosphine borane compounds was performed under PTC to obtain C-60…