Lithium Chloride → 1-(t-Butyloxycarbonyl)-4-(4-methylbenzothiazol-2-yl)-2-methyl-1,2,5,6-tetrahydropyridine

Participants

Reaction Conditions

Reaction Steps

Scheme IIA, Step A: To a mixture of 2-chloro-4-methylbenzothiazole (1.052 g, 5.73 mmol) in 1,4-dioxane (60 mL) was added 1-(t-butyloxycarbonyl)-2-methyl-4-trifluoromethanesulfonyl-1,2,5,6-tetrahydropyridine (2.077 g, 6.01 mmol), hexamethylditin (1.876 g, 5.73 mmol), tetrakis(triphenylphosphine)palladium (0.331 g, 0.286 mmol) and lithium chloride (0.729 g, 17.2 mmol). The mixture was heated at reflux for 20 hours, then cooled to 20° C. and diluted with saturated potassium fluoride and ethyl acetate. The mixture was stirred for 2 hours, then partitioned, and the organics were washed with brine dried over sodium sulfate and evaporated. The residue was chromatographed over silica gel (hexanes/50% ethyl acetate in hexanes gradient elution) to give the intermediate title compound as a yellow amorphous solid (1.3 g, 66%). FDMS m/e=345 (M++1).

Provenance & Evidence