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ChemicalBook CAS DataBase List (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-ol
156928-09-5

(3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-ol synthesis

4synthesis methods
-

Yield:156928-09-5 82%

Reaction Conditions:

Stage #1:(3S,3aS,6aR)-3-hydroxyhexahydrofuro[2,3-b]furan with di-isopropyl azodicarboxylate;triphenylphosphine;4-nitro-benzoic acid in benzene at 23; for 1.5 h;Mitsunobu reaction;
Stage #2: with lithium hydroxide;triethylamine in methanol;water at 20; for 2 h;

Steps:

Preparation of bis-THF derivative (I) (by Mitsunobu inversion of compound (5) )
To a stirred solution of alcohol (5) (400 mg, 3.07 mmol), tri- phenylphosphine (1.6 g, 61.4 mmol), and p-nitroben- zoic acid (770 mg, 4.61 mmol) in dry benzene (30 mL) at [23°C] was added diisoproylazodicarboxylate (DIAD, 1.2 mL, 6.14 mmol) dropwise. After 1.5 hours, the mixture was concentrated in vacuo, and the crude ester was dissolved in a (4: 3: 1) mixture of MeOH : Et3N: H20 [(24] mL), then treated with [LIOH] [(450] mg, 10.7 mmol). The solution was stirred at room temperature for 2 h. The mixture then was con- centrated under reduced pressure-and the residue was chromatographed over silica gel to provide the bis- THF [(I)] (326 mg, 82%); [[A]] [25D-12.] 4 (c 1.16, [MEOH).]

References:

THE BOARD OF TRUSTEES OF THE UNIVERSITY OF ILLINOIS WO2004/33462, 2004, A2 Location in patent:Page 40; 41

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