cl 2 to give the desired aldehyde 30 4 68 g 21 8 mmol 87 as a colorless oil 1 h nmr 9 85 t 1 h j 1 hz h 4 6 65 t 1 h j 5 hz h 1 2 08 s 6 h ch 3ac 2 01 m 2 h h 3 1 85 s 6 h ch 3 13 c nmr 201 05 c 4 168 72 c och 3 89 65 c 1 42 80 c 3 37 42 c 2 21 50 c h 3 20 35 c h 3ac analysis calc 39 d for c 10 h 16 o 5 c 55 55 h 7 46 this compound was prepared in four steps from anhydrous glycerol by monoalkylation oxidation of the diol acetylation and ozonolysis koh 11 2 g 200 mmol was added cautiously to anhydrous glycerol 60 ml 821 mmol in a 250 ml flask and the mixture was heated to 60 u00b0 c under a nitrogen atmosphere until the koh had dissolved after cooling to room temperature allyl bromide 17 3 ml 20 mmol was added over 15 min dropwise with stirring and the mixture was stirred at 90 u00b0 c for 14 h after cooling to room temperature the mixture was diluted with aqueous 50 k 2 co 3 100 ml then extracted with ch 2 cl 2 3 u00d7 100 ml the combined extracts were dried filtered and evaporated the residual diol a colorless oil 22 5.