Water → Lansoprazole

Participants

Reaction Conditions

Reaction Steps

For example, in Example 22 of this publication, it is described that a mixture, which was obtained by adding water (3.6 mmol), (+)-diethyl L-tartrate (15.0 mmol) and titanium(IV) isopropoxide (6.0 mmol) to a solution of 2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]thio]-1H-benzimidazole (6.0 mmol) in toluene, stirring the resulting mixture at 50° C. for 60 min, cooling the reaction mixture to room temperature, adding N,N-diisopropylethylamine (6.0 mmol) and cumene hydroperoxide (6.0 mmol) and stirring the mixture at room temperature for 16 hr, consisted of 13% of sulfide, 8% of sulfone and 76% of sulfoxide as determined by achiral HPLC, that post-treatments of purification by flash chromatography and the like gave (+)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-1H-benzimidazole (0.85 g) showing 46%ee enantiomer excess, and that, by further purification, 0.31 g (14%) of the objective substance having an optical purity of 99.6%ee was ultimately obtained as an oily substance.

Provenance & Evidence