(3aS,4S,6aR)-2,2-dimethyl-3a,4,6,6a-tetrahydrothieno[3,4-d][1,3]dioxole-4-carbaldehyde

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

Procedure: To a solution of 111 (2.1 g, 11.1 mmol) in pyridine (20 mL) was added benzoyl chloride (1.9 g, 13.4 mmol) at 0° C. and the reaction mixture was stirred for 6 h at room temperature before being quenched with methanol. The reaction mixture was evaporated under reduced pressure. The residue was then taken up in diethyl ether (50 mL), and the pyridinium salt was filtered and washed with diethyl ether. The combined organic layer was concentrated and the resulting residue was purified by silica gel column chromatography (hexane/ethyl acetate=4:1) to afford the benzoate 112 (3.2 g, 99%) as a colorless oil: 1H NMR (CDCl3) δ 1.26 (s, 3H, CH3), 1.47 (s, 3H, CH3), 2.87 (dd, 1H, J=13.2, 1.5 Hz, 6-CHH), 3.11 (dd, 1H, J=13.2, 4.9 Hz, 6–CHH), 3.57 (m, 1H, 4-H), 4.25 (dd, 1H, J=11.5, 8.0 Hz, BzOCHH), 4.35 (dd, 1H, J=11.4, 5.8 Hz, BzOCHH), 4.72 (dd, 1H, J=5.6, 1.2 Hz, 6a-H), 4.91 (td, 1H, J=4.4, 1.2 Hz, 3a-H), 7.35–7.99 (m, 5H, Ph); FAB-MS m/z 294 (M+); Anal. Calcd for C15H18O4S: C, 61.20; H, 6.16; S, 10.89. Found: C, 60.99; H, 6.42; S, 10.77. before being quenched with methanol The reaction mixture was evaporated under reduced pressure the pyridinium salt was filtered washed with diethyl ether The combined organic layer was concentrated the resulting residue was purified by silica gel column chromatography (hexane/ethyl acetate=4:1)

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

Procedure: 2.8 g (0.015 mol) of (3aS,4S,6aR)-2,2-dimethyltetrahydrothieno[3,4-d][1,3]dioxole-4–Carbaldehyde from the aforementioned Experimental Example 6 were dissolved in 200 mL of anhydrous N,N-dimethylformamide to which 26.7 g (0.070 mol) of pyridinium dichromate was added. The reaction mixture was stirred at ambient temperature for 20 h. After 0.3 L of water were added, it was extracted with 2.5 L of ethyl acetate (0.5 L×5). The extract was dried, filtered, and concentrated under reduced pressure to obtain the concentrate which was (3aS,4S,6aR)-2,2-dimethyltetrahydrothieno[3,4-d][1,3]dioxole-4-carboxylic acid. The concentrate was dissolved in 65 mL of acetone to which 2 mL (21.14 mmol) of dimethyl sulfate and 1.2 g (8.68 mmol) of potassium carbonate were added. The resulting mixture was stirred for 2 h. Acetone was distilled off under reduced pressure, and the residue was dissolved in ethyl acetate, followed by washing with water and saturated saline solution. The organic layer was dried and filtered, and the filtrate was concentrated under reduced pressure. The concentrate was purified by silica gel column chromatography using the eluant (hexane:ethyl acetate=3:1) mixture to obtain 2.5 g (yield: 78%) of (3aS,4S,6aR)-2,2-dimethyltetrahydrothieno[3,4-d][1,3]dioxole-4-carboxylic acid methyl ester as an oil. was added it was extracted with 2.5 L of ethyl acetate (0.5 L×5) The extract was dried filtered concentrated under reduced pressure to obtain the concentrate which were added The resulting mixture was stirred for 2 h Acetone was distilled off under reduced pressure the residue was dissolved in ethyl acetate by washing with water and saturated saline solution The organic layer was dried filtered the filtrate was concentrated under reduced pressure The concentrate was purified by silica gel column chromatography

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

Procedure: 2.5 g (11.2 mmol) of (1R)-1-((3aS,4R,6aR)-2,2-dimethyltetrahydrothieno[3,4-d][1,3]dioxol-4-yl)-ethane-1,2-diol from the aforementioned Experimental Example 5 were dissolved in ethyl acetate to which lead tetraacetate were added at 0° C., and the reaction mixture was stirred for 10 min. The reaction mixture was filtered. Ethyl acetate was added to the filtrate, which was washed with saturated sodium bicarbonate, dried, and filtered. The filtrate was concentrated under reduced pressure, and the concentrate was purified by silica gel column chromatography using the eluant (hexane:ethyl acetate=5:1) to obtain 2.1 g (yield: 98%) of (3aS,4S,6aR)-2,2-dimethyltetrahydrothieno[3,4-d][1,3]dioxole-4–Carbaldehyde as an oil. were added at 0° C. The reaction mixture was filtered Ethyl acetate was added to the filtrate, which was washed with saturated sodium bicarbonate dried filtered The filtrate was concentrated under reduced pressure the concentrate was purified by silica gel column chromatography