1,4,4a,5,6,7,8,8a-octahydroisochromen-3-one

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2.0 g (13 mmol) of (4a alpha, 8a alpha)(rac)-octahydro-3H-2-benzopyran-3-one in 65 mL of dry dichloromethane was added dropwise, over 30 min, 14 mL (14.3 mmol) of a 1.0 M solution of diisobutylaluminum hydride in dichloromethane. After further stirring at -78° C. for 45 min the mixture was warmed to 0° C. over 2 hours, stirred at 0° C. for 10 min, and then 1.0M aqueous HCl was added dropwise until a pH 0-1 was reached. After addition of 60 mL of ether, phase separation and extraction of the aqueous portion with 3×50 mL of ether, the combined organic solutions were washed with 5% KHCO3, dried (MgSO4) and concentrated under vacuum to 1.60 g (80%) of racemic (4a alpha, 8a alpha)-octahydro-1H-2-benzopyran-3-ol. TLC Rf 0.41 (SiO2, ether, molybdophosphoric acid-blue). was warmed to 0° C. over 2 hours stirred at 0° C. for 10 min the combined organic solutions were washed with 5% KHCO3 dried (MgSO4) concentrated under vacuum to 1.60 g (80%) of racemic (4a alpha, 8a alpha)-octahydro-1H-2-benzopyran-3-ol

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 3.16 g (23 mmol) of (3a alpha, 7a alpha )-octahydro-2H-inden-2-one, 17.3 g (207 mmol) of NaHCO3 and 300 mL of dichloromethane was added 9.29 g of 85% m. chloroperoxybenzoic acid in small portions over 15 min. The reaction mixture was stirred for 17 h at 20° C., then 200 mL of 10% aqueous Na2S2O3 was added and, after 15 min, the organic phase was separated. Extraction of the aqueous portion with 2×100 mL of dichloromethane, washing of the combined organic solutions with 10% Na2CO3 and concentration of the dried (MgSO4) solutions under vacuum 9ave 3.51 9 (95%) of racemic (4a alpha, 8a alpha)-octahydro-3H-2-benzopyran-3-one. TLC Rf 0.40 (SiO2, ethyl ether, iodine-brown). was added 9.29 g of 85% m the organic phase was separated Extraction of the aqueous portion with 2×100 mL of dichloromethane washing of the combined organic solutions with 10% Na2CO3 and concentration of the dried (MgSO4) solutions under vacuum 9ave 3.51 9 (95%) of racemic (4a alpha, 8a alpha)-octahydro-3H-2-benzopyran-3-one

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2.0 g (13 mmol) of (4a alpha, 8a alpha)(rac)-octahydro-3H-2-benzopyran-3-one in 65 mL of dry dichloromethane was added dropwise, over 30 min, 14 mL (14.3 mmol) of a 1.0M solution of diisobutylaluminum hydride in dichloromethane. After further stirring at -78° C. for 45 min the mixture was warmed to 0° C. over 2 hours, stirred at 0° C. for 10 min, and then 1.0M aqueous HCl was added dropwise until a pH 0-1 was reached. After addition of 60 mL of ether, phase separation and extraction of the aqueous portion with 3×50 mL of ether, the combined organic solutions were washed with 5% KHCO3, dried (MgSO4) and concentrated under vacuum to 1.60 g (80%) of racemic (4a alpha, 8a alpha)-octahydro-1H-2-benzopyran-3-ol. TLC Rf 0.41 (SiO2, ether, molybdophosphoric acid-blue). was warmed to 0° C. over 2 hours stirred at 0° C. for 10 min the combined organic solutions were washed with 5% KHCO3 dried (MgSO4) concentrated under vacuum to 1.60 g (80%) of racemic (4a alpha, 8a alpha)-octahydro-1H-2-benzopyran-3-ol

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 3.16 g (23 mmol) of (3a alpha, 7a alpha)-octahydro-2H-inden-2-one, 17.3 g (207 mmol) of NaHCO3 and 300 mL of dichloromethane was added 9.29 g of 85% m. chloroperoxybenzoic acid in small portions over 15 min. The reaction mixture was stirred for 17 h at 20° C., then 200 mL of 10% aqueous Na2S2O3 was added and, after 15 min, the organic phase was separated. Extraction of the aqueous portion with 2×100 mL of dichloromethane, washing of the combined organic solutions with 10% Na2CO3 and concentration of the dried (MgSO4) solutions under vacuum gave 3.51 g (95%) of racemic (4a alpha, 8a alpha)-octahydro-3H-2-benzopyran-3-one. TLC Rf 0.40 (SiO2, ethyl ether, iodine-brown). was added 9.29 g of 85% m the organic phase was separated Extraction of the aqueous portion with 2×100 mL of dichloromethane washing of the combined organic solutions with 10% Na2CO3 and concentration of the dried (MgSO4) solutions under vacuum