Sodium Hydroxide → 3-(3-Quinolyl)-2-propen-1-ol t-butyl carbonate

Participants

Reaction Steps

3-(3-quinolyl)-2-propen-1-ol t-butyl carbonate was prepared as follows. To a 500-mL three-necked round-bottom flask equipped with an overhead mechanical stirrer was charged 3-(3-quinolyl)-2-propen-1-ol (13.03 g, 70.43 mmol) as a mixture of cis and trans isomers (81% cis, and 19% trans), di-t-butyl dicarbonate (16.91 g, 77.48 mmol, 1.11 equiv), tetra n-butyl ammonium hydrogensulfate (742 mg, 2.17 mmol) and methylene chloride (135 mL). The stirred mixture was cooled to 0 to 5° C. at which time aqueous 25% sodium hydroxide (33.3 mL) was added over 45 minutes such that the internal temperature did not rise above 20° C. Upon completion of the reaction (1 to 4 hours), the reaction mixture was diluted with methylene chloride (50 mL) and washed with water (2×125 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to provide the 3-(3-quinolyl)-2-propen-1-ol t-butyl carbonate: 18.35 g (91.4%) as an oil. This material can be further purified by chromatography on silica gel to provide purified carbonate as a colorless oil which retains the original ratio of cis and trans isomers: 17.50 g, 87.2%.

Provenance & Evidence