.beta.-Methylstyrene

Conditions: temp:23.01; pressure:0.00; stir:; After dropwise addition of dimethoxy(methyl)- silane into reaction mixture in water bath, the vessel was removed and allowed to stir for an additional 12 hours

Procedure: 3 x 50 mL ethyl acetate extraction rotary evaporator (35 degC, 50 mmHg) The crude reaction mixture is dissolved in a minimal quantity of benzene or toluene and is loaded onto a column, with interior diameter of roughly 2 inches, packed with silica (200 g, SiliCycle, F60/230-400 mesh) and equilibrated with hexanes. The column is eluted under air pressure with hexanes (500 mL), then 1% ethyl acetate in hexanes (1 L), then 2% ethyl acetate in hexanes (1 L). During elution, fractions are collected in test tubes (roughly 28 mL each), and the desired product typically elutes around fractions 18 through 66. The fractions that contain the productare combined rotary evaporator (30 degC, 80 mmHg) blue orange

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The metal-catalyzed epoxidation of trans-β-methylstyrene was performed as described in Example 2 with the substitution of [Ru3O(pfb)6 (Et2O)3 ](pfb) (where pfb= perfluorobutyrate) (0.0449 g, 2.3×10-5 moles) as the catalyst. After 6 hours of reaction, the complete oxidation of the substrate produced benzaldehyde (30%) and 1-phenylpropylene oxide (70%). After 6 hours of reaction

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The metal-catalyzed epoxidation of trans-β-methylstyrene was performed as described in Example 2 with the substitution of Co(OAc)2. 4 H2O (where OAc=acetate) (0.0058 g, 2.3×10-5 moles) as the catalyst. After 16 hours of reaction, the complete oxidation of the substrate produced benzaldehyde (14%) and 1-phenylpropylene oxide (86%). After 16 hours of reaction

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Unlike CF3COCH3, which gives higher conversion at high pH, acetone catalyzed epoxidation reactions proceeded at much faster rate at a lower pH (about 8.3). Because the decomposition of H2O2 was not very fast at this pH, the reaction can be done at room temperature. Although controlled experiment showed that significant amount of epoxidation also occurred in the absence of acetone at this pH (Payne epoxidation), the addition of acetone allowed the epoxidation to proceed much faster and gave higher conversion. For example, a 41% conversion of trans-β-methylstyrene was obtained in the absence of acetone after stirred at room temperature for 10 h. However, in the presence of acetone, an 83% yield of trans-β-methylstyrene oxide could be obtained after stirring for 5 h. Table 4 lists additional examples using acetone under similar conditions. the reaction can be done at room temperature gave higher conversion

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: According to GP, 2.22 mmol (=0.36 g=0.34 ml) of phenylpiperazine and 2.22 mmol (=0.26 g=0.29 ml) of β-trans-methylstyrene are reacted with 5 mol % (=0.111 mmol=70 μl) of n-BuLi solution. Column-chromatographic separation with ethyl acetate/n-hexane (3:1) gives the product 1-phenyl-4-(1-methyl-2-phenylethyl)piperazine as a yellow solid. Column-chromatographic separation with ethyl acetate/n-hexane (3:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: According to GP, 2.22 mmol (=0.36 g=0.34 ml) of phenylpiperazine and 2.22 mmol (=0.26 g=0.29 ml) of β-trans-methylstyrene are reacted with 5 mol % (=0.111 mmol=70 μl) of n-BuLi solution. Column-chromatographic separation with ethyl acetate/n-hexane (3:1) gives the product 1-phenyl-4-(1-methyl-2-phenylethyl)piperazine as a yellow solid. Column-chromatographic separation with ethyl acetate/n-hexane (3:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The metal-catalyzed epoxidation of trans-β-methylstyrene was performed as described in Example 2 with the substitution of [Ru3O(pfb)6 (Et2O)3 ](pfb) (where pfb= perfluorobutyrate) (0.0449 g, 2.3×10-5 moles) as the catalyst. After 6 hours of reaction, the complete oxidation of the substrate produced benzaldehyde (30%) and 1-phenylpropylene oxide (70%). After 6 hours of reaction

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The metal-catalyzed epoxidation of trans-β-methylstyrene was performed as described in Example 2 with the substitution of [Ru3O(pfb)6 (Et2O)3 ](pfb) (where pfb= perfluorobutyrate) (0.0449 g, 2.3×10-5 moles) as the catalyst. After 6 hours of reaction, the complete oxidation of the substrate produced benzaldehyde (30%) and 1-phenylpropylene oxide (70%). After 6 hours of reaction

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The metal-catalyzed epoxidation of trans-β-methylstyrene was performed as described in Example 2 with the substitution of Co(OAc)2. 4 H2O (where OAc=acetate) (0.0058 g, 2.3×10-5 moles) as the catalyst. After 16 hours of reaction, the complete oxidation of the substrate produced benzaldehyde (14%) and 1-phenylpropylene oxide (86%). After 16 hours of reaction

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The metal-catalyzed epoxidation of trans-β-methylstyrene was performed as described in Example 2 with the substitution of Co(OAc)2. 4 H2O (where OAc=acetate) (0.0058 g, 2.3×10-5 moles) as the catalyst. After 16 hours of reaction, the complete oxidation of the substrate produced benzaldehyde (14%) and 1-phenylpropylene oxide (86%). After 16 hours of reaction

Conditions: temp:-10.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Reaction at −10° C.: trans-β-methylstyrene (0.181 g, 1 mmol) was dissolved in acetonitrile/DMM (15 mL, ½, V/V). Buffer (10 mL, 0.05 M solution of Na2B4O7.H2O in 4×10−4 M aqueous Na2EDTA), tetrabutylammonium hydrogen sulfate (15 mg, 0.04 mmol), and ketone 1 (0.0774 g, 0.3 mmol) were added with stirring. The mixture was cooled to about −10° C. via a NaCl-ice bath. A solution of Oxone® (0.85 g, 1.38 mmol) in aqueous Na2EDTA (4×10−4 M, 6.5 mL) and a solution of K2CO3 (0.8 g, 5.8 mmol) in water (6.5 mL) were added dropwise separately over a period of 2 h (via syringe pumps or addition funnels). The reaction was then worked up by the same procedure as Method B to afford trans-β-methylstyrene oxide (0.126 g, 94% yield, 95.5% ee). Reaction at −10° C. (via syringe pumps or addition funnels)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 100 mL three-neck round bottom flask, were added buffer (0.05 M Na2B4O7.10H2O in 4×10−4 M aq. Na2EDTA, 10 mL), acetonitrile (15 mL), trans-β-methylstyrene (0.118 g, 1 mmol), tetrabutylammonium hydrogen sulfate (0.015 g, 0.04 mmol), and ketone 1 (0.0774 g, 0.3 mmol). The reaction mixture was cooled by an ice bath. A solution of Oxone® (0.85 g, 1.38 mmol) in aq. Na2EDTA (4×10−4 M, 6.5 mL) and a solution of K2CO3 (0.8 g, 5.8 mmol) in water (6.5 mL) were added dropwise through two separate addition funnels over a period of 1.5 h (under this condition, the reaction pH is around 10.5. At this point, the reaction was immediately quenched by addition of pentane and water. The mixture was extracted with pentane (3×30 mL), washed with brine, dried over Na2SO4, purified by flash chromatography [the silica gel was buffered with 1% Et3N in pentane, pentane/ether (1/0 to 50/1, V/V) was used as eluent] to afford trans-β-methylstyrene oxide as colorless liquid (0.124 g, 93% yield, 92% ee). The reaction mixture was cooled by an ice bath separate addition funnels over a period of 1.5 h (under this condition the reaction pH is around 10.5 At this point, the reaction was immediately quenched by addition of pentane and water The mixture was extracted with pentane (3×30 mL) washed with brine dried over Na2SO4 purified by flash chromatography [the silica gel