4-phenylbutan-2-yl acetate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: Into a four-necked flask provided with a thermometer and a stirrer, 150 g (1 mol) of 4-phenyl-2-butanol (XXX-35), 500 ml of toluene and 200 ml of pyridine were charged. 122.4 g (1.2 mol) of anhydrous acetic acid and 1 g of 4-dimethylaminopyridine were further added thereto to react them for 4 hours, while temperature being maintained at 40°-50° C. After completion of the reaction, the reaction mixture was poured into 500 ml of 4N hydrochloric acid solution, extracted and fractionated, and then an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order. The thus-obtained Organic layer was concentrated under a reduced pressure to obtain 189 g of 2-acetoxy-4-phenylbutane (XXIX-35) with yield of 98.5%. were charged to react them for 4 hours while temperature being maintained at 40°-50° C After completion of the reaction extracted an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order The thus-obtained Organic layer was concentrated under a reduced pressure

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

Procedure: Into a four-necked flask provided with a thermometer and a stirrer, 150 g (1 mol) of 4-phenyl-2-butanol (XXX-35), 500 ml of toluene and 200 ml of pyridine were charged. 122.4 g (1.2 mol) of anhydrous acetic acid and 1 g of 4-dimethylaminopyridine were further added thereto to react them for 4 hours, while temperature being maintained at 40°-50° C. After completion of the reaction, the reaction mixture was poured into 500 ml of 4N hydrochloric acid solution, extracted and fractionated, and then an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order. The thus-obtained Organic layer was concentrated under a reduced pressure to obtain 189 g of 2-acetoxy-4-phenylbutane (XXIX-35) with yield of 98.5%. were charged to react them for 4 hours while temperature being maintained at 40°-50° C After completion of the reaction extracted an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order The thus-obtained Organic layer was concentrated under a reduced pressure

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

Procedure: Into a four-necked flask provided with a thermometer and a stirrer, 150 g (1 mol) of 4-phenyl-2-butanol (XXX-35), 500 ml of toluene and 200 ml of pyridine were charged. 122.4 g (1.2 mol) of anhydrous acetic acid and 1 g of 4-dimethylaminopyridine were further added thereto to react them for 4 hours, while temperature being maintained at 40°-50° C. After completion of the reaction, the reaction mixture was poured into 500 ml of 4N hydrochloric acid solution, extracted and fractionated, and then an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order. The thus-obtained Organic layer was concentrated under a reduced pressure to obtain 189 g of 2-acetoxy-4-phenylbutane (XXIX-35) with yield of 98.5%. were charged to react them for 4 hours while temperature being maintained at 40°-50° C After completion of the reaction extracted an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order The thus-obtained Organic layer was concentrated under a reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: Into a four-necked flask provided with a thermometer and a stirrer, 150 g (1 mol) of 4-phenyl-2-butanol (XXX-35), 500 ml of toluene and 200 ml of pyridine were charged. 122.4 g (1.2 mol) of anhydrous acetic acid and 1 g of 4-dimethylaminopyridine were further added thereto to react them for 4 hours, while temperature being maintained at 40°-50° C. After completion of the reaction, the reaction mixture was poured into 500 ml of 4N hydrochloric acid solution, extracted and fractionated, and then an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order. The thus-obtained organic layer was concentrated under a reduced pressure to obtain 189 g of 2-acetoxy-4-phenylbutane (XXIX-35) with yield of 98.5%. were charged to react them for 4 hours while temperature being maintained at 40°-50° C After completion of the reaction extracted an organic layer was washed with 1N hydrochloric acid, water, 5% sodium bicarbonate solution and water in the order The thus-obtained organic layer was concentrated under a reduced pressure

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

Procedure: This reaction was performed as in Example 1 with bis(cyclooctadienyl)rhodium tetrafluoroborate (20 mg; 0.05 mmol; 0.02 equiv), R,R-1,2-bis(2,5-dimethylphospholano)benzene (6, R"=CH3 ; 18 mg; 0.06 mmol; 0.024 equiv) and 4-phenylbut-1-en-2-yl acetate (476 mg; 2.5 mmol) in 20 mL of degassed THF until hydrogen uptake ceased (1.5 h) to afford 0.51 g of crude product. 1H NMR analysis indicated 4-phenyl-2-butyl acetate as the sole product, and chiral GC analysis and comparison to racemate indicated 77% ee for 4-phenyl-2-butyl acetate. Base hydrolysis afforded 4-phenyl-2-butanol, [α]D25 -12.0° (c 2.115, CHCl3), which indicates the (R) configuration when compared with the known rotation ([α]D +13.5° (c 2.1, CHCl3)) for the (S) enantiomer. (1.5 h) to afford 0.51 g of crude product Base hydrolysis

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

Procedure: This reaction was performed as in Example 1 with bis(cyclooctadienyl)rhodium tetrafluoroborate (10 mg; 0.025 mmol; 0.02 equiv), R,R-1,2-bis(2,5-dimethylphospholano)benzene (6, R"=CH3 ; 9 mg; 0.03 mmol; 0.024 equiv) and 4-phenylbut-1-en-3-yn-2-yl acetate (3b; 233 mg; 1.25 mmol) in 10 mL of degassed THF until hydrogen uptake ceased to afford 0.25 g of crude product. 1H NMR analysis indicated Z-4-phenyl-3-buten-2-yl acetate (5b) as the sole product, and reduction of the olefin to afford 4-phenyl-2-butyl acetate followed by chiral GC analysis and comparison to the racemate and authentic R-4-phenyl-2-butyl acetate indicated 97.8% ee for R-Z-4-phenyl-3-buten-2-yl acetate. Further investigation indicated a bimodal reduction, with 4-phenylbut-1-en-3-yn-2-yl acetate initially chemoselectively and enantioselectively reduced to 4-phenylbut-3-yn-2-yl acetate (4b), which was then more slowly reduced to Z-4-phenyl-3-buten-2-yl acetate (5b). to afford 0.25 g of crude product