CC1C=CC(S([O:11][CH2:12][C@@H:13]2[CH2:18][O:17][C@@H:16]([CH:19]=[CH2:20])[CH2:15][O:14]2)(=O)=O)=CC=1.O.[OH-].[Na+]>C([O-])(=O)C.C([N+](CCCC)(CCCC)CCCC)CCC.CN(C)C=O.CCOC(C)=O>[CH:19]([C@H:16]1[CH2:15][O:14][C@H:13]([CH2:12][OH:11])[CH2:18][O:17]1)=[CH2:20]A solution of ((2S,5S)-5-vinyl-1,4-dioxan-2-yl)methyl 4-methylbenzenesulfonate (2.0 g, 6.70 mmol, Preparation #11) and tetrabutylammonium acetate (2.63 g, 8.71 mmol) in dimethylformamide (5 mL) were heated at about 70° C. for about 3 h. The reaction mixture was cooled to RT and the reaction vessel was charged sequentially with water (2 mL) and 1.0 N aqueous sodium hydroxide (4.0 mL). After stirring for about 20 min at RT, the mixture was diluted with EtOAc with (20 mL) and washed with brine solution (2×20 mL). The organic layer was dried over sodium sulphate and concentrated under reduced pressure. The crude material obtained was purified by column chromatography eluting with 30-40% EtOAc in hexane. The relevant fractions containing product were combined and concentrated to afford ((2R,5S)-5-vinyl-1,4-dioxan-2-yl)methanol. 0.7 g (72.4%). 1H NMR (400 MHz, CDCl3): δ 5.77-5.68 (m, 1H), 5.38-5.22 (m, 2H), 4.04-3.99 (m, 1H), 3.86-3.81 (m, 2H), 3.68-3.52 (m, 4H), 3.44-3.38 (m, 1H); IR (Neat):3433 cm−1 (OH str)
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