I([O-])(=O)(=O)=O.[Na+].[CH2:7]1[CH2:11][O:10][CH2:9][CH2:8]1>O.[Os](=O)(=O)(=O)=O>[CH2:7]([C:7]1[C:11](=[O:10])[CH2:8][CH2:9][C:8]=1[CH:9]=[O:10])[CH3:11]15.4 g (0.113 mole) of the vinyl compound 4 in 320 ml of THF was added to a 1-liter, round-bottom flask equipped with a 250 ml addition funnel and magnetic stirring bar. 4.4. ml of a solution prepared by solution of 0.783 g of osmium tetraoxide in 50 ml water was added dropwise. The mixture was stirred for 20 minutes and then a solution of 50.7 g (0.237 mole) sodium periodate in 396 ml of water was added over a 40-minute period. After completion of the addition the mixture was stirred for one hour and then filtered through a sintered glass funnel, using CHCl3 to wash the precipitate. The filtrate was extracted with CHCl3 and the combined chloroform extracts dried over anhydrous sodium sulfate (NaSO4). The CHCl3 was removed under reduced pressure to yield 15.0 g (0.109 mole, 96.2%) of a dark green crude liquid (aldehyde 5); uv max (95% ethanol) 247 and 256 nm; ir (neat) 1710 and 1670 cm-1 (C=O); nmr (CDCl3) δ9.7 (s, 1, C--H) and 1.2 (t, 3, --CH2 --CH3).
Wird geladen…
