Water → (3R,3aS,6S,6aS)-6-Bromohexahydrofuro[3,2-b]furan-3-yl 4-methylbenzenesulfonate

HRID 1715074Notes

Reaction equation

[C:1]([Br:5])(Br)(Br)Br.[CH3:6][C:7]1[CH:12]=[CH:11][C:10]([S:13]([O:16][C@@H:17]2[CH2:21][O:20][C@@H:19]3[C@H](O)[CH2:23][O:24][C@H:18]23)(=[O:15])=[O:14])=[CH:9][CH:8]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.O>N1C=CC=CC=1>[CH3:6][C:7]1[CH:12]=[CH:11][C:10]([S:13]([O:16][C@@H:17]2[CH2:21][O:20][C@@H:19]3[C@@H:1]([Br:5])[CH2:23][O:24][C@H:18]23)(=[O:15])=[O:14])=[CH:9][CH:8]=1

Participants

Conditions

Temperature: 65 °C

Procedure

A solution of carbon tetrabromide (18.12 g, 54.63 mmol) in pyridine (100 mL) was added to a solution of monotosylate (50) (14.9 g, 49.66 mmol) and triphenylphosphine (26.1 g, 99.32 mmol) in pyridine (150 mL) over 30 minutes, then the mixture heated at 65° C. for 1.5 hours under an atmosphere of argon. Water (200 mL) was added then the aqueous phase extracted with dichloromethane (5×100 mL). The organic phase was washed with brine (50 mL), then dried (MgSO4), filtered and reduced in vacuo to leave a residue which was azeotroped with toluene (5×50 mL). Flash chromatography over silica, eluting with diethyl ether:heptane mixtures 0:100 to 100:0 gave bromotosylate (46) (7.70 g, 43%) as a white solid. [α]D17+68.60 (c=0.51, CHCl3).

Workup

extractionthe aqueous phase extracted with dichloromethane (5×100 mL)
washThe organic phase was washed with brine (50 mL)
dry with materialdried (MgSO4)
filtrationfiltered
customto leave a residue which
customwas azeotroped with toluene (5×50 mL)
washFlash chromatography over silica, eluting with diethyl ether

Sources & evidence

ORD record: ord-a064799c545e4d81a0027e95e434f7f1
Source dataset: uspto-grants-2010_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07799791B2

Reaction notes

Loading…