(R)‐ and (S)‐2,2′‐Bis(bis(3,5‐dimethylphenyl)phosphanyl)‐1,1′‐binaphthalene

[137219-86-4] C52H48P2 (MW 734.89) InChI = 1S/C52H48P2/c1-33-21-34(2)26-43(25-33)53(44-27-35(3)22-36(4)28-44)49-19-17-41-13-9-11-15-47(41)51(49)52-48-16-12-10-14-42(48)18-20-50(52)54(45-29-37(5)23-38(6)30-45)46-31-39(7)24-40(8)32-46/h9-32H,1-8H3 InChIKey = MXGXXBYVDMVJAO-UHFFFAOYSA-N [135139-00-3] C52H48P2 (MW 734.89) InChI = 1S/C52H48P2/c1-33-21-34(2)26-43(25-33)53(44-27-35(3)22-36(4)28-44)49-19-17-41-13-9-11-15-47(41)51(49)52-48-16-12-10-14-42(48)18-20-50(52)54(45-29-37(5)23-38(6)30-45)46-31-39(7)24-40(8)32-46/h9-32H,1-8H3 InChIKey = MXGXXBYVDMVJAO-UHFFFAOYSA-N (axial chiral diphosphine ligand for enantioselective transition metal catalysis, ruthenium catalysts for asymmetric hydrogenations, catalysts for asymmetric addition to alkenes and alkynes, asymmetric cycloadditions, asymmetric cycloisomerizations, and asymmetric fluorination) Alternative Names: xylBINAP, xyl-BINAP, xylyl-BINAP, m-xylyl-BINAP, 3,5-xylyl-BINAP, 3,5-diMe-BINAP, DM-BINAP, 1,1′-[(1S)-[1,1′-binaphthalene]-2,2′-diyl]bis[1,1-bis(3,5-dimethylphenyl)-phosphine. Physical Data: mp 286–288 °C; (c = 1.00, CHCl3) for (S)-xylBINAP 1-3 Solubility: no data available. Form Supplied in: white to pale yellow solid. Analysis of Reagent Purity: proof of purity is determined by proton, carbon, and phosphorus NMR, infrared spectrum, melting point, and optical rotation (polarimeter). The optical purity can be determined after oxidation to xylBINAPO by HPLC using a CHIRACEL OD column, eluting with 9:1 hexane/isopropanol (0.5 mL min−1): Rt = 8.3 min (R)-BINAPO, Rt = 11.2 min (S)-BINAPO.2 Preparative Methods: The original synthesis of enantioenriched xylBINAP is a multistep sequence beginning with addition of the bis-Grignard reagent prepared from racemic 2,2′-dibromo-1,1′-binaphthalene to bis(3,5-dimethylphenyl)phosphinyl chloride (prepared from the corresponding phosphonic acid). The resultant racemic xylBINAPO oxide is resolved with O,O′-dibenzoyl tartaric acid via multiple recrystallizations. After a salt break with sodium hydroxide, the enantioenriched xylBINAPO is deoxygenated with trichlorosilane and triethylamine in xylene at 130 °C.2 Enantiomerically enriched xylBINAP can also be prepared by nickel-catalyzed coupling of the corresponding enantioenriched binaphthy 2,2′-ditriflate with either bis(3,5-dimethylphenyl)phosphine, bis(3,5-dimethylphenyl)chlorophosphine, or bis(3,5-dimethylphenyl)bromophosphine and zinc metal after 2–3 days at 110 °C.4, 5 Purification: final purification by chromatography. Handling, Storage, and Precautions: air and moisture stable as the crystalline solid. Incompatible with oxidizing agents.6