Development of New P-Chiral P,π-Dihydrobenzooxaphosphole Hybrid Ligands for Asymmetric Catalysis

Abstract

A new family of P-chiral P,π-hybrid ligands was prepared from the dihydrobenzooxaphosphole core. These new ligands were demonstrated to be both sterically and electronically tunable at the substituents on the phosphorus atom and the π-system of the ligand. Application of these new ligands to the catalytic asymmetric addition of boronic acids to imine electrophiles was shown to proceed with high levels of enantioinduction.

Enantiodivergent Formation of C–P Bonds: Synthesis of P-Chiral Phosphines and Methylphosphonate Oligonucleotides

“…If, however, only one reagent was in hand, simply changing the order of addition in this modular strategy could lead to either enantiomer of coupling or displacement products (vide infra). Some notable substrates emerging from this route include 26, aka PAMPO, which is a precursor to important ligand scaffolds such as DiPAMP 9a and JoshPhos 15 . Compounds 27 and 29, previously prepared through diastereomeric separation, are used in the enantioselective synthesis of allylic alcohols and phenyl sulfides.…”

Rhodium‐Catalyzed Asymmetric Allenylation of Sulfonylimines and Application to the Stereospecific Allylic Allenylation

“…Recently, we have disclosed a new family of P ‐chiral P ,π‐hybrid ligands (Joshphos, L1 ) that are applicable in the asymmetric addition of arylboronic acids to N ‐tosylaldimines enabled by Rh‐boron exchange between the boronic acid nucleophile and the Rh catalyst . We reasoned that application of this catalytic system to Rh‐boron exchange with 4 might enable an alternative asymmetric method to access 1c (PG=Ts) from imine 5 .…”

The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2014

“…157) for total synthesis of penarolide sulfate A2 [509]; (21) a 1,5-diene ester derivative and an allylic alcohol derivative [510]; (22) styrene derivatives with a vinyltetrahydropyran for preparation of rhoiptelol B [511], with allylic diol for preparation of ginger diols [512], and with an alkene-phosphine oxide (e.g. 159) for preparation of ligands for asymmetric catalysis [513]; (23) an allylbenzene derivative and a homoallylic alcohol derivative for total synthesis of rhoiptelol C [514]; (24) the benzyl ester of 2,2-dimethyl-3-butenoate (162) and an allyltetrahydrofuran derivative (e.g. 161) for preparation of the spiroacetal core of cephalosporolides [515]; (25) vinylcyclopropane dicarboxylate esters (e.g.…”