(S)-(−)-2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl, a versatile chelating ligand

Abstract

The crystal structure of the title compound, [(S)‐(−)‐BINAP] or C44H32P2, is enantiomorphous to the previously reported (R)‐(+)‐BINAP [Deeming et al. (1997). Organometallics, 16, 6004–6009], with effectively no differences in the molecular geometry apart from being of opposite absolute configuration.

rac-2,2′-Bis(diphenylphosphanyl)-1,1′-binaphthyl: a racemic diphosphine ligand

“…The asymmetric unit is one half of complete chiral BINAP molecule, the symmetry related part being generated by a twofold rotational axis running along b and across the middle of two moities in the molecule (Fig 1). This structure is similar to the previously reported one for the (S)-enantiomer (S)-(-)-2,2′-Bis(diphenylphosphanyl)-1,1′-binaphthyl (Jones et al 2003). In the present case, however, there are inversion centers relating molecules into racemic pairs.…”

“…For similar diphosphine ligands, see: Kassube et al (2008); Fawcett et al (2005); Wu et al (2004). For the related crystal structure of the (S)-enantiomer (S)-(À)-2,2 0 -bis(diphenylphosphanyl)-1,1 0 -binaphthyl, see: Jones et al (2003). Data collection: CrysAlis PRO (Oxford Diffraction, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.…”

“…Among them, 2,2′-Bis(diphenylphosphanyl)-1,1′-binaphthyl (BINAP), a diphosphine ligand, is well known for its chirality, and has been used as chiral catalyst in various asymmetry catalyzed reaction (Kojima et al 2012;Aikawa et al 2011;Ge et al 2011;Moran et al 2011). Previously, Jones M. D. etc reported the crystal structure of the (S)-enantiomer (S)-(-)-2,2′-Bis(diphenylphosphanyl)-1,1′-binaphthyl (Jones et al 2003). But the crystal structure of the racemic BINAP crystal had not been reported so far.…”

(S)-(−)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole

“…This ligand has been used on palladium for the catalysis of ketone-ene reactions (Aikawa et al, 2004). All bond lengths and angles in (I) are normal and are comparable to those in the related compound (S)-(-)-2,2′-Bis(diphenylphosphino) -1,1′-binaphthyl (Jones et al, 2003). The key feature of (I) is the intramolecular P•••P distance of 3.671 (2) Å and the two benzene rings in the biphenyl moiety make a dihedral angle of 77.9 (2)°.…”

1,1′-Biisoquinolines—Neglected Ligands in the Heterocyclic Diimine Family That Provoke Stereochemical Reflections

“…It is instructive to use ligand 6 to illustrate the consequences of coordination. The free ligand is non-planar as a consequence of the interactions between the 2-PPh 2 and 2′-PPh 2 substituents and also between H8 and H8′; this is seen in the solid-state structures of (2 P )- 6 ( P 2 1 ) [ 36 , 37 ] (2 M )- 6 ( P 2 1 ) [ 37 , 38 ] and rac - 6 ( C 2/ c ) [ 37 , 39 ] which have all been reported. In all cases the two aromatic rings of the 1,1′-binaphthalene scaffold are close to orthogonal in the solid state with torsion angles C2–C1–C1′–C2′ in the range 91.536–93.429°.…”