3,3-dimethyldioxirane

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:

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

Conditions: temp:-50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of desoxyepothilone B (0.0022 g, 0.0041 mmol) in CH2Cl2 (0.25 mL) at −50° C. was added dimethyidioxirane (0.1 mL, 0.0095 mmol) dropwise. The resulting solution was stirred at −50° C. for 1 h. The dimethyldioxirane and solvent were removed by a stream of N2. The residue was purified by flash column chromatography (hexanes/ethyl acetate, 1:1) gave 0.0015 g (70%) of epothiolone B (2) as a pale yellow oil which was identical with an authentic sample in 1H NMR, IR, mass spectrum, and [α]D. The dimethyldioxirane and solvent were removed by a stream of N2 The residue was purified by flash column chromatography (hexanes/ethyl acetate, 1:1)

Conditions: temp:-50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of desoxyepothilone B (0.0022 g, 0.0041 mmol) in CH2Cl2 (0.25 mL) at −50° C. was added dimethyldioxirane (0.1 mL, 0.0095 mmol) dropwise. The resulting solution was stirred at −50° C. for 1 h. The dimethyldioxirane and solvent were removed by a stream of N2. The residue was purified by flash column chromatography (hexanes/ethyl acetate, 1:1) gave 0.0015 g (70%) of epothiolone B (2) as a pale yellow oil which was identical with an authentic sample in 1H NMR, IR, mass spectrum, and [α]D. The dimethyldioxirane and solvent were removed by a stream of N2 The residue was purified by flash column chromatography (hexanes/ethyl acetate, 1:1)

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

Procedure: A solution of 0.051 M dimethyldioxirane in acetone (32.9 ml, 1.67 mmol) was added to a cold stirred solution of N,N-dibenzylamine (Aldrich; 0.331 g, 1.67 mmol) in acetone (5 ml). The mixture was stirred for fifteen minutes in an ice bath. Evaporation of the solvent on the rotary evaporator gave a white crystalline solid. The solid was dissolved in acetone and the solution dried with anhydrous Na2SO4. The solvent was removed to give a chromatographically homogeneous white solid (0.352 g, 98% yield). Measured mp was 121-122; reported mp is 122-123 (DeLaMare et al 1963). Evaporation of the solvent on the rotary evaporator gave a white crystalline solid the solution dried with anhydrous Na2SO4 The solvent was removed

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

Procedure: Following the general procedure of Example 2 and using 8.56 g (18.5 mmol) of N-(2,6-diphenyl-3,5-dimethylpiperidin-4-yl)lauramide, prepared in Example 11, and 462 ml of a 0.04 molar solution of dimethyldioxirane (18.5 mmol) in acetone, the title compound is isolated in a yield of 7.37 g (70%) after purification by LC (silica gel; ethyl acetate:hexanes) as a white solid melting at 58°-62° C.

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

Procedure: Following the general procedure of Example 2 and using 8.56 g (18.5 mmol) of N-(2,6-diphenyl-3,5-dimethylpiperidin-4-yl)lauramide, prepared in Example 11, and 462 ml of a 0.04 molar solution of dimethyldioxirane (18.5 mmol) in acetone, the title compound is isolated in a yield of 7.37 g (70%) after purification by LC (silica gel; ethyl acetate:hexanes) as a white solid melting at 58°-62° C.

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

Procedure: The general procedure of Example 2 is repeated using 29.9 g (64.5 mmol) of 2,6-diphenyl-3,5-dimethylpiperidin-4-yl laurate and 1.24 L (64.5 mmol) of dimethyldioxirane (0.050M in acetone). 30.8 g (98% yield) of the title compound is isolated: mp 108°-112° C.