1-[(R)-(1,1-Dimethylethyl)sulfinyl]-2-(1-phenylethenyl)benzene

[1335243-44-1] C18H20OS (MW 284.12) InChI = 1S/C18H20OS/c1-14(15-10-6-5-7-11-15)16-12-8-9-13-17(16)20(19)18(2,3)4/h5-13H,1H2,2-4H3/t20-/m0/s1 InChIKey = XXRPLVIIEDGADV-FQEVSTJZSA-N (reagent used as a ligand in the asymmetric catalysis)1-4 Physical Data: mp 105–106 °C; [ α ] D 20 = + 87 ( c 0.10 , CHCl 3 ) . Solubility: ethyl acetate, dichloromethane, and most organic solvents. Form Supplied in: white solid. Purification: column chromatography. Analysis of Reagent Purity: 1H NMR, 13C NMR, and HRMS. Preparative Method: to the mixture of methyl triphenylphosphonium bromide (7.40 g, 20.1 mmol) and t-BuOK (3.7 g, 33.0 mmol) was added anhydrous THF (40.0 mL) and the solution was stirred at room temperature for 20 min under argon atmosphere. A solution of 2-bromobenzophenone 1 (2.61 g, 10.0 mmol) in THF (20.0 mL) was added slowly, and the reaction solution was allowed to stir at room temperature for overnight. Following a quench with saturated NH4Cl, the THF was removed and the aqueous solution was extracted with EtOAc (3 × 30 mL). The combined EtOAc solution was washed with brine, dried over anhydrous Na2SO4. After removing the solvent under reduced pressure, the residue was purified by flash chromatography to yield 2 (2.59 g, 100%) as a colorless oil (eq 1). To the solution of 2 (2.10 g, 8.1 mmol) in THF (40 mL) was added n-BuLi (3.9 mL, 2.5 M in hexane, 9.6 mmol) dropwise at −78 °C. The solution was allowed to stir at this temperature for 0.5 h after which a solution of (R)-tert-butyl tert-butanethiosulfinate 3 (1.42 g, 7.3 mmol) in THF (20.0 mL) was added dropwise and the mixture was slowly warmed to room temperature. After 1.5 h, the reaction was quenched with saturated NH4Cl, and then the solution was concentrated under reduced pressure. The residue was dissolved in EtOAc (60 mL); layers were separated, and the aqueous layer was extracted with EtOAc (3 × 20 mL). The combined organic layer was dried over anhydrous Na2SO4. After removing the solvent under reduced pressure, the residue was purified by chromatography to give 4 (1.10 g, 48%) as a white solid (eq 2). (1) (2)