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ChemicalBook CAS DataBase List 2,5-O-METHYLENE-D-MANNITOL
36566-49-1

2,5-O-METHYLENE-D-MANNITOL synthesis

1synthesis methods
-

Yield:36566-49-1 1.0 kg (67%)

Reaction Conditions:

with sodium methylate in chloroform;

Steps:

5.3 Part 3

Part 3 2,5-O-methylene-D-mannitol (Scheme VI; 18) 1,3,4,6-Tetra-O-acetyl-2,5-O-methylene-D-mannitol 17 (2.8 kg, 7.73 mol) was added to chloroform (14 lit.) in 25 lit. round bottom flask with mechanical stirring. The reaction mixture was cooled to 0° C., and 0.5% NaOMe solution (6.5 lit.) was added slowly. The reaction mixture was stirred for 3 hours. The solid was filtered and dried to provide 1.0 kg (67%) of 2,5-O-methylene-D-mannitol 18, m.p. 172°-173° C., [α]D -52° C. 1.18, CHCl3), TLC (silica gel), 1:4, methanol: chloroform, Rf=0.8. 1H-NMR (D20): δ3.42 (m, 2H), 3.72 (m, 4 H), 3.97 (m, 2 H), 4.91 (s, 2 H).

References:

US6310221,2001,B1

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