6-bromo-3,4-dihydrochromen-2-one

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

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

Procedure: To a mixture of 16.4 g (72.2 mmole) 6-bromo-2chromanone and 60 ml dry tetrahydrofuran, under nitrogen at -70° C., was added a cloudy solution of 18.4 g (72.2 mmole) lithium hydrido-tri(t-butoxy)aluminate (commercial) over 30 minutes. The mixture was stirred while allowing it to warm to room temperature over 90 minutes, then poured onto 250 ml ice/water. The resulting mixture was filtered, the cake washed with ethyl ether, then ethyl acetate and the organic phase is separated. The aqueous layer is extracted with ethyl acetate, the organic layers combined, dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product. An additional 4 g was obtained by reworking the filter cake, above. The combined crude products were purified on a silica gel column, eluting with 9:1 hexane/ethyl acetate, then a 4:1 mixture of the same solvents to obtain the purified product as an oil, 5.6 g. The resulting mixture was filtered the cake washed with ethyl ether ethyl acetate and the organic phase is separated The aqueous layer is extracted with ethyl acetate dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product An additional 4 g was obtained were purified on a silica gel column eluting with 9:1 hexane/ethyl acetate a 4:1 mixture of the same solvents

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

Procedure: To a mixture of 16.4 g (72.2 mmole) 6-bromo-2chromanone and 60 ml dry tetrahydrofuran, under nitrogen at -70° C., was added a cloudy solution of 18.4 g (72.2 mmole) lithium hydrido-tri(t-butoxy)aluminate (commercial) over 30 minutes. The mixture was stirred while allowing it to warm to room temperature over 90 minutes, then poured onto 250 ml ice/water. The resulting mixture was filtered, the cake washed with ethyl ether, then ethyl acetate and the organic phase is separated. The aqueous layer is extracted with ethyl acetate, the organic layers combined, dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product. An additional 4 g was obtained by reworking the filter cake, above. The combined crude products were purified on a silica gel column, eluting with 9:1 hexane/ethyl acetate, then a 4:1 mixture of the same solvents to obtain the purified product as an oil, 5.6 g. The resulting mixture was filtered the cake washed with ethyl ether ethyl acetate and the organic phase is separated The aqueous layer is extracted with ethyl acetate dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product An additional 4 g was obtained were purified on a silica gel column eluting with 9:1 hexane/ethyl acetate a 4:1 mixture of the same solvents

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

Procedure: To a solution of 74.08 g (0.50 mole) 2-chromanone in 150 ml carbon disulfide at 0° C. was added dropwise over 15 minutes, 79.91 g (0.50 mole) bromine. Stirring was continued at 0° C. for ten minutes and at room temperature for 2 days. The resulting mixture was filtered, the crystals air dried to afford 96.8 g (85%) of colorless material, m.p. 103°-105° C. (2 crops). The resulting mixture was filtered the crystals air dried

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

Procedure: To a solution of 74.08 g (0.50 mole) 2-chromanone in 150 ml carbon disulfide at 0° C. was added dropwise over 15 minutes, 79.91 g (0.50 mole) bromine. Stirring was continued at 0° C. for ten minutes and at room temperature for 2 days. The resulting mixture was filtered, the crystals air dried to afford 96.8 g (85%) of colorless material, m.p. 103°-105° C. (2 crops). The resulting mixture was filtered the crystals air dried

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

Procedure: To a mixture of 16.4 g (72.2 mmole) 6-bromo-2chromanone and 60 ml dry tetrahydrofuran, under nitrogen at -70° C., was added a cloudy solution of 18.4 g (72.2 mmole) lithium hydrido-tri(t-butoxy)aluminate (commercial) over 30 minutes. The mixture was stirred while allowing it to warm to room temperature over 90 minutes, then poured onto 250 ml ice/water. The resulting mixture was filtered, the cake washed with ethyl ether, then ethyl acetate and the organic phase is separated. The aqueous layer is extracted with ethyl acetate, the organic layers combined, dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product. An additional 4 g was obtained by reworking the filter cake, above. The combined crude products were purified on a silica gel column, eluting with 9:1 hexane/ethyl acetate, then a 4:1 mixture of the same solvents to obtain the purified product as an oil, 5.6 g. The resulting mixture was filtered the cake washed with ethyl ether ethyl acetate and the organic phase is separated The aqueous layer is extracted with ethyl acetate dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product An additional 4 g was obtained were purified on a silica gel column eluting with 9:1 hexane/ethyl acetate a 4:1 mixture of the same solvents

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

Procedure: To a solution of 74.08 g (0.50 mole) 2-chromanone in 150 ml carbon disulfide at 0° C. was added dropwise over 15 minutes, 79.91 g (0.50 mole) bromine. Stirring was continued at 0° C. for ten minutes and at room temperature for 2 days. The resulting mixture was filtered, the crystals air dried to afford 96.8 g (85%) of colorless material, m.p. 103°-105° C. (2 crops). The resulting mixture was filtered the crystals air dried

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

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

Procedure: 4-(4-propylcyclohexyl)phenylboronic acid (1.3 g), 6-bromo-3,4-dihydrocoumarin (1.0 g), potassium carbonate (1.2 g), tetrakistriphenylphosphine-palladium (51 mg), and tetrabutylammonium bromide (10 mg) were suspended in DME (10 ml), and the suspension was stirred under reflux by heating for 3 hours. After completion of the reaction, the reaction mixture was added in ice water and extracted with toluene. An organic layer was washed with water and then dried over anhydrous magnesium sulfate. The solution was concentrated in vacuo and then subjected to isolation and purification by silica gel column chromatography, thereby obtaining a titled compound (500 mg). As a result of a variety of instrumental analyses, it was confirmed that this was the titled compound. under reflux by heating for 3 hours After completion of the reaction extracted with toluene An organic layer was washed with water dried over anhydrous magnesium sulfate The solution was concentrated in vacuo subjected to isolation and purification by silica gel column chromatography

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

Procedure: To a mixture of 16.4 g (72.2 mmole) 6-bromo-2chromanone and 60 ml dry tetrahydrofuran, under nitrogen at -70° C., was added a cloudy solution of 18.4 g (72.2 mmole) lithium hydrido-tri(t-butoxy)aluminate (commercial) over 30 minutes. The mixture was stirred while allowing it to warm to room temperature over 90 minutes, then poured onto 250 ml ice/water. The resulting mixture was filtered, the cake washed with ethyl ether, then ethyl acetate and the organic phase is separated. The aqueous layer is extracted with ethyl acetate, the organic layers combined, dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product. An additional 4 g was obtained by reworking the filter cake, above. The combined crude products were purified on a silica gel column, eluting with 9:1 hexane/ethyl acetate, then a 4:1 mixture of the same solvents to obtain the purified product as an oil, 5.6 g. The resulting mixture was filtered the cake washed with ethyl ether ethyl acetate and the organic phase is separated The aqueous layer is extracted with ethyl acetate dried (Na2SO4) and solvent evaporated to obtain 9.5 g crude product An additional 4 g was obtained were purified on a silica gel column eluting with 9:1 hexane/ethyl acetate a 4:1 mixture of the same solvents

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

Procedure: To a solution of 74.08 g (0.50 mole) 2-chromanone in 150 ml carbon disulfide at 0° C. was added dropwise over 15 minutes, 79.91 g (0.50 mole) bromine. Stirring was continued at 0° C. for ten minutes and at room temperature for 2 days. The resulting mixture was filtered, the crystals air dried to afford 96.8 g (85%) of colorless material, m.p. 103°-105° C. (2 crops). The resulting mixture was filtered the crystals air dried