Supporting Text Synthesis of (2 S ,3 S )-2,3-bis(3-bromophenoxy)butane (3). Synthesis of (2 S ,3 S

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1 Supporting Text Synthesis of (2S,3S)-2,3-bis(3-bromophenoxy)butane (3). Under N 2 atmosphere and at room temperature, a mixture of 3-bromophenol (0.746 g, 4.3 mmol) and Cs 2 C 3 (2.81 g, 8.6 mmol) in DMS (5 ml) was stirred for 1 h, then a solution of (2R,3R)-butanediol dimesylate (0.531 g, 2.2 mmol) in DMS (10 ml) was added dropwise into this mixture over a period of 4 h. The mixture was continuously stirred at 55 C for 8 h before pouring into water (100 ml). The organic phase was extracted with CH 2 Cl 2. The extract was treated with 2 N HCl solution (10 ml) and washed with water and brine again. The organic layer was separated, dried over Na 2 S 4, and concentrated in vacuo. The residue was purified through a silica gel column to give a colorless oil 3 (0.461 g, 1.15 mmol, 53% yield). 1 H NMR (500 MHz, CDCl 3 ): δ = 1.36 (d, J = 6.0 Hz, 6H), (m, 2H), (m, 2H) and (m, 6H). 13 C NMR (125 MHz, CDCl 3 ): δ = 15.27, 76.34, , , , , and HRMS (EI + VE + LMR): calcd for C 16 H 16 Br 2 2 [M] , found [α] 20 D = 22.6 (c = 1, CHCl 3 ). Synthesis of (2S,3S)-2,3-bis[3-(diphenylphosphoryl)phenoxy]butane (5). Compound 3 (1.80 g, 4.50 mmol) was azeotropically dried with dry toluene (15 ml 2) and dissolved in dry tetrahydrofuran (THF) (100 ml). n-buli (9.45 mmol, 1.6 M solution in hexane) was added dropwise into the solution at 78 C within 30 min under N 2. After stirring for an additional 1 h at this temperature, chlorodiphenyl phosphine (1.8 ml, 9.45 mmol) in THF (5 ml) was added dropwise to the resulting mixture. The reaction was continued at 78 C for 1 h and then at room temperature overnight. The resulting light-yellow solution was extracted with CH 2 Cl 2 /water. The organic phase was separated, washed with water and brine, and dried over Na 2 S 4. After evaporation of the solvent, a light-yellow solid was obtained. The residue was purified by silica gel column chromatography to give a colorless oily solid 4. An aqueous H 2 2 solution (30%, 6.0 ml) was added to a solution of compound 4 in acetone (20 ml) at 0 C. The reaction was monitored by thin-layer chromatography. The product was extracted with dichloromethane twice. The combined extract was washed successively with Na 2 S 2 3 solution, water, and brine, dried over anhydrous Na 2 S 4, and was concentrated in vacuo to give a crude product. Purification by silica gel column chromatography afforded a pure colorless solid 5 (2.46 g, 3.83 mmol, 85% yield based on 3). 1 H NMR (500 MHz, CDCl 3 ): δ = 1.26 (d, J = 5.5 Hz, 6H), (m, 2H), (m, 2H), (dd, J = 11.8 Hz, 7.8 Hz, 2H), (m, 4H), (m, 8H), (m, 4H) and (m, 8H). 31 P NMR (202 MHz, CDCl 3 ): δ = C NMR (125 MHz, CDCl 3 ): δ = 15.06, 76.03, , , , , , , , , , , , , , , , , , and HRMS (ESI): calcd for C 40 H 37 P 2 4 [M + H] , found ; [α] 20 D = 19.6 (c = 1, CHCl 3 ). Preparation of RuLCl 2 (DMF) n. To a Schlenk tube with a magnetic stirring bar was charged with [RuCl 2 (benzene)] 2 (2.0 mg, mmol), ligand 8 (5.4 mg, mmol), 2,2 -bis(diphenylphosphino)-6,6 -dimethoxy-1,1 -biphenyl (Me-BIPHEP) (4.9 mg, mmol) or (S)-2,2 -bis(diphenylphosphino)-1,1 -binaphthyl (S-BINAP) (5.3

2 mg, mmol), and degassed dry dimethylformamide (DMF) (2.0 ml). The resulting solution was heated at 100 C for 30 min and then was concentrated in vacuo to give the catalyst as a reddish-brown solid. Preparation of [RuL(p-cymene)Cl]Cl. To a mixture of the ligand (8 8.4 mg, S-BINAP 8.6 mg, or Me-BIPHEP 8.1 mg, mmol) and [Ru(p-cymene)Cl 2 ] 2 (3.7 mg, mmol) in a Schlenk tube was added ethanol (3.0 ml) and CH 2 Cl 2 (1.0 ml). The resulting mixture was stirred at 50 C for 1 h and was filtered. The orange-yellow filtrate was concentrated in vacuo to give the catalyst as an orange solid. [Ru(R)-8(p-cymene)Cl]Cl: 1 H NMR (500 MHz, CD 2 Cl 2 ): δ = 0.90 (d, J = 6.5 Hz, 3H), 1.12 (d, J = 6.5 Hz, 3H), 1.16 (d, J = 6.0 Hz, 3H), 1.29 (d, J = 7.0 Hz, 3H), 1.87 (s, 3H), (m, 1H), (m, 1H), (m, 1H), 6.02 (d, J = 7 Hz, 1H), 6.58 (d, J = 8 Hz, 1H) and (m, 28 H). 31 P NMR (202 MHz, CDCl 3 ): δ = (d, J = 65.8 Hz), (d, J = 65.8 Hz). Preparation of [Ru8(η 6 -C 6 H 6 )Cl]Cl. Preparation method of catalyst [Ru8(η 6 - C 6 H 6 )Cl]Cl was similar to that for [RuL(p-cymene)Cl]Cl using [Ru(benzene)Cl 2 ] 2 and ligand 8 as starting materials. [Ru8(η 6 -C 6 H 6 )Cl]Cl: 1 H NMR (500 MHz, CD 2 Cl 2 ): δ = 1.17 (d, J = 6.5 Hz, 3H), 1.18 (d, J = 6.5 Hz, 3H), (m, 1H), (m, 1H), 5.80 (s, 6H) and (m, 26H). 31 P NMR (202 MHz, CD 2 Cl 2 ): δ = (d, J = 68.4 Hz), (d, J = 68.4 Hz). Preparation of (NMe 2 H 2 )[(Ru8Cl) 2 (µ-cl) 3 ]. To a mixture of the ligand 8 (10 mg, mmol) and [Ru(benzene)Cl 2 ] 2 (4.1 mg, mmol) in a Schlenk tube was added ethanol (3.0 ml) and CH 2 Cl 2 (1.0 ml). The resulting mixture was stirred at 50 C for 1 h. The solvent was removed in vacuo, then dimethylamine hydrochloride (1.4 mg, mmol) and dioxane (5 ml) were added. The mixture was stirred under reflux for 15 h. The reaction solution was concentrated in vacuo to dryness to afford the catalyst as a brown solid. (NMe 2 H 2 )[(Ru8Cl) 2 (µ-cl) 3 ]: 1 H NMR (500 MHz, CD 2 Cl 2 ): δ = 1.20 (d, J = 6 Hz, 6 H), 1.29 (d, J = 6.5 Hz, 6H), 3.56 (s, 6H), (m, 2H), (m. 2H), (m, 2H), (d, 8 Hz, 2H), (m, 4H), (m, 2H), (m, 6H), 6.89 (t, J = 8 Hz, 2 H), (m, 6 H), (m, 12 H), (m, 8H), 7.86 (t, J = 8.3 Hz, 4H) and (broad s, 6 H). 31 P NMR (202 MHz, CD 2 Cl 2 ): δ = (d, J = 38.8 Hz), (d, J = 38.8 Hz). General Procedure for the Asymmetric Hydrogenation of β-ketoesters. A glass-lined stainless steel autoclave was charged with β-ketoester (0.5 mmol), RuLCl 2 (DMF) n ( mmol), CH 2 Cl 2 (12.5 µl) and methanol or ethanol (987.5 µl) under nitrogen atmosphere. The mixture was stirred well with a magnetic stirrer at a certain temperature under 50 psi H 2. Conversions of the substrates and enantiomeric excesses of the products

3 were determined by GC after converting the products to the corresponding acetyl derivatives or by HPLC. General Procedure for the Asymmetric Hydrogenation of α-ketoester. A glass-lined stainless steel autoclave was charged with α-ketoester (0.5 mmol), [Ru8(η 6 -C 6 H 6 )Cl]Cl ( mmol), and methanol (1 ml) under nitrogen atmosphere. The mixture was stirred well with a magnetic stirrer at a certain temperature under a certain hydrogenation pressure. Conversions of the substrates and enantiomeric excesses of the products were determined by GC. General Procedure for the Asymmetric Hydrogenation of 2-(6 -Methoxy-2 - naphthyl)propenoic Acid. A glass-lined stainless steel reactor was charged with 5.0 mg of 2-(6 -methoxy-2 -naphthyl)propenoic acid, mmol [RuL(p-cymene)Cl]Cl catalyst and 2.5 ml of methanol. The solution was stirred well with a magnetic stirrer at a certain temperature under a chosen hydrogen pressure. Conversion of the substrate and enantiomeric excess of the product were determined by HPLC with a Sumichiral A column. General Procedure for the Asymmetric Hydrogenation of β-(acylamino)acrylates. A glass-lined stainless steel autoclave was charged with β-(acylamino)acrylates (1.7 mg), [Ru8(η 6 -C 6 H 6 )Cl]Cl (S/C = 100:1) and methanol under nitrogen atmosphere. The mixture was stirred well with a magnetic stirrer at a certain temperature under 250 psi H 2. Conversions of the substrates and enantiomeric excesses of the products were determined by GC. General Procedure for the Asymmetric Hydrogenation of Enol Acetates. A glasslined stainless steel autoclave was charged with enol acetates (0.1 mmol) in ethanol (1.0 ml) and (NMe 2 H 2 )[(Ru8Cl) 2 (µ-cl) 3 ] ( mmol) in CH 2 Cl 2 (0.25 ml) under nitrogen atmosphere. The mixture was stirred well with a magnetic stirrer at a room temperature (rt) to 50 C under 50 psi H 2. Conversions of the substrates and enantiomeric excesses of the products were determined by chiral GC with a Varian 25 m 0.25 mm CP- CYCLDEX B 236M column.

4 1 H NMR (500 MHz, CDCl 3 ) of 3 Br Br

5 13 C NMR (125 MHz, CDCl 3 ) of 3 Br Br

6 1 H NMR (500 MHz, CDCl 3 ) of 5 Ph 2 ()P Ph 2 ()P

7 31 P NMR (202 MHz, CDCl 3 ) of 5 Ph 2 ()P Ph 2 ()P

8 13 C NMR (125 MHz, CDCl 3 ) of 5 Ph 2 ()P Ph 2 ()P

9 1 H NMR (500 MHz, CDCl 3 ) of 6 Ph 2 P() Ph 2 P() I I

10 31 P NMR (202 MHz, CDCl 3 ) of 6 Ph 2 P() Ph 2 P() I I