P-chirogenic phosphines. MOP/diPAMP hybrids, their oxide crystal structures, reduction studies and alternative syntheses

2-Diphenylphosphino-2′-hydroxybiphenyl-based P-ligands and their platinum(II) complexes

“…As an analogy, 2-(anisylphenylphosphino)-2 0 -methoxy-1,1 0 -binaphthyl has been described that was obtained from the corresponding phosphine oxide by deoxygenation using phenylsilane. It is worthy of mention that after a reduction over 3 days at 80°C, partial epimerisation of the P-centrum occurred [12].…”

The synthesis of P-stereogenic MOP analogues and their use in rhodium catalysed asymmetric addition

“…The ligands were synthesised using a variation of the methodology previously developed by our group (Scheme 1) [8]. This method proceeds via the mono-triflation of optically pure (R)-BINOL using N-phenyl-bis(trifluoromethanesulfonamide).…”

“…Also deboronation is much more convenient and reliable for retention of configuration than phosphine oxide reduction, which was required when we previously separated similar compounds as the oxides [8]. The route also offered the advantage that a number of phosphines could be tested in the nickel coupling reaction to give a series of chiral ligands (Table 1).…”

“…Previously our group have reported the novel synthesis of P-stereogenic MOP analogues ( Fig. 1) [8,9]. These ligands contain anisyl and phenyl substituents on the stereogenic phosphorus, creating a hybrid of the P-chiral DiPAMP and Hayashi's axially chiral MOP [10,11] ligand.…”

The Primary Phosphine Renaissance

“…As part of our research into P-stereogenic MOP derivatives [37], we wished to synthesize the chiral primary phosphine precursors (R)-2-phosphino-2 0 -methoxy-1,1 0 -binaphthyl (R)-5 and the H-MOPH 2 analogue (S)-2-phosphino-1,1 0 -binaphthyl (S)-6. Both were prepared by following the methodology shown in Fig.…”