Phanephos (original) (raw)

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Phanephos
Names
IUPAC name (S)-(+)-4,12-Bis(diphenylphosphino)-[2.2]-paracyclophane; (R)-(−)-4,12-Bis(diphenylphosphino)-[2.2]-paracyclophane
Other names(S)-Phanephos; (R)-Phanephos
Identifiers
CAS Number (S): 364732-88-7 checkY(R): 192463-40-4 checkY
3D model (JSmol) (S): Interactive image
ChemSpider (S): 9040059
ECHA InfoCard 100.217.129 Edit this at Wikidata
EC Number (R): 690-034-8
PubChem CID (S): 10864772
CompTox Dashboard (EPA) (S): DTXSID301045593 Edit this at Wikidata
InChI InChI=1S/C40H34P2/c1-5-13-35(14-6-1)41(36-15-7-2-8-16-36)39-29-31-21-25-33(39)27-23-32-22-26-34(28-24-31)40(30-32)42(37-17-9-3-10-18-37)38-19-11-4-12-20-38/h1-22,25-26,29-30H,23-24,27-28H2Key: GYZZZILPVUYAFJ-UHFFFAOYSA-N(S): InChI=1/C40H34P2/c1-5-13-35(14-6-1)41(36-15-7-2-8-16-36)39-29-31-21-25-33(39)27-23-32-22-26-34(28-24-31)40(30-32)42(37-17-9-3-10-18-37)38-19-11-4-12-20-38/h1-22,25-26,29-30H,23-24,27-28H2Key: GYZZZILPVUYAFJ-UHFFFAOYAH
SMILES (S): C1CC2=C(C=C(CCC3=C(C=C1C=C3)P(C4=CC=CC=C4)C5=CC=CC=C5)C=C2)P(C6=CC=CC=C6)C7=CC=CC=C7
Properties
Chemical formula C40H34P2
Molar mass 576.660 g·mol−1
Appearance White to off-white powder or crystals
Melting point 222 to 225 °C (432 to 437 °F; 495 to 498 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chemical compound

Phanephos is an organophosphorus compound with the chemical formula (C2H4)2(C6H3PPh2)2 (Ph = C6H5). It is a white solid that is soluble in organic solvents. It is an example of a chiral C2-symmetric diphosphine ligand used in asymmetric hydrogenation. Many substituents have been introduced in place of the phenyl groups, e.g., _i_-Pr, C6H11, etc. and a variety of chiral diphosphine ligands have been reported in asymmetric catalysis since the 1960s.

Phanephos can be prepared in two steps from [2.2]paracyclophane. In the first step, [2.2]paracyclophane is dibrominated to give a pseudo-para dibromide. Thermal isomerisation then gives pseudo-ortho atropisomer of the dibromide. This isomer is subjected to lithium-halogen exchange by nBuLi and the resulting dilithium compound is treated with PPh2Cl to give a racemic mixture of phanephos.[1]

Phanephos preparation

Phanephos has been used in rhodium- and ruthenium- mediated stereoselective hydrogenation of dehydro amino acid methyl esters and asymmetric reduction of various β-ketoesters with about 90% ee.[2]

  1. ^ G. J. Rowlands, Planar Chiral Phosphines Derived from [2.2]Paracyclophane , Israel Journal of Chemistry, 2012, 52. 60-75, doi:10.1002/ijch.201100098
  2. ^ R. Gleiter, H. Hopf, Modern Cyclophane Chemistry, Wiley-VCH Verlag GmbH & Co. KGaA, 2005, p.449-451 doi:10.1002/3527603964