反应详情

A solution of 32.9 g (80 mmol) of trans-[4-(2,2-dibromo-vinyl)-cyclohexylmethyl]-methyl-carbamic acid tert-butyl ester in 640 ml tetrahydrofuran was treated at −78° C. with 105 ml (168 mmol) of n-butyl-lithium (ca 1.6 M in hexane). After 2 hours at this temperature, 24 g (800 mmol) of paraformaldehyde were added. The reaction mixture was warmed up to room temperature for 3 hours and after 0.5 hours at this temperature extracted with water/ether (3×). The organic phases were washed with aqueous 10% NaCl, dried over sodium sulfate and evaporated. Purification by flash-chromatography on silica gel (hexane/EtOAc 9:1 to 2:1) yielded 12.1 g (54%) of trans-[4-(3-hydroxy-prop-1-ynyl)-cyclohexylmethyl]-methyl-carbamic acid tert-butyl ester as orange viscous oil, MS: 282 (MH+).

1. extractionextracted with water/ether (3×)
2. washThe organic phases were washed with aqueous 10% NaCl
3. dry with materialdried over sodium sulfate
4. customevaporated
5. customPurification by flash-chromatography on silica gel (hexane/EtOAc 9:1 to 2:1)