Hexane → 2-t-Butyloxycarbonylamino-1-cyclohexylbut-3-ene

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of methyltriphenyl phosphonium bromide (10.97 g, 30.70 mmol) in anhydrous tetrahydrofuran (200 ml) at -78° C. (dry ice/acetone bath) under an argon atmosphere, was added n-butyl lithium (19.8 ml of a 1.55M hexane solution) dropwise over the course of 5 min. After 10 min, the -78° C. bath was replaced with a 0° C. bath for 0.5 h, at which time the resulting orange solution was cooled again to -78° C. The solution was then added dropwise by cannula to a stirred -78° C. solution of Boc-cyclohexylalaninal (27.91 mmol) in anhydrous tetrahydrofuran (30 ml) over the course of 0.5 h. The mixture was then allowed to warm to room temperature during a 3 h period after which water (150 ml) was added. Extraction with hexane (4×100 ml) provided a combined organic phase which was washed with brine (100 ml), dried (Na2SO4), and concentrated. Chromatography with ether/hexane (1/9) provided the desired compound. Mass spectrum: (M+H)+ =254.

Provenance & Evidence