Ammonia → (3S,4R)-4-amino-3,4-dihydro-3-hydroxy-6-(3-hydroxyphenyl)sulphonyl-2,2,3-trimethyl-2H-benzo[b]pyran

HRID 1416187Notes

Reaction equation

[Si]([O:8][C:9]1[CH:10]=[C:11]([S:15]([C:18]2[CH:31]=[CH:30][C:21]3[O:22][C:23]([CH3:29])([CH3:28])[C@@:24]4([CH3:27])[O:26][C@H:25]4[C:20]=3[CH:19]=2)(=[O:17])=[O:16])[CH:12]=[CH:13][CH:14]=1)(C(C)(C)C)(C)C.[NH3:32]>C(O)C>[NH2:32][C@H:25]1[C@@:24]([OH:26])([CH3:27])[C:23]([CH3:29])([CH3:28])[O:22][C:21]2[CH:30]=[CH:31][C:18]([S:15]([C:11]3[CH:12]=[CH:13][CH:14]=[C:9]([OH:8])[CH:10]=3)(=[O:17])=[O:16])=[CH:19][C:20]1=2

Participants

Conditions

Temperature: 45 °C

Procedure

(3S,4S)-6-(3-tert-Butyldimethylsilyloxyphenyl)sulphonyl-3,4-dihydro-3,4-epoxy-2,2,3-trimethyl-2H-benzo[b]pyran (2.2 g) (see Preparation 15) was dissolved in ethanol (25 ml) and 35% aqueous ammonia solution (25ml) was added. The mixture was heated at 40-50° C. for 24 hours. The solvent was removed under reduced pressure and the residue was chromatographed on silica using 7.5:92.5 methanol: dichloromethane as the eluent to yield (3S,4R)-4-amino-3,4-dihydro-3-hydroxy-6-(3-hydroxyphenyl)sulphonyl-2,2,3-trimethyl-2H-benzo[b]pyran (1.42 g) as a foam. Found: C,54.39; H,5.22; N,3.19. C18H21NO5S, 0.50 CH2Cl2 requires C,54.75; H,5.46; N,3.45%.

Workup

customThe solvent was removed under reduced pressure
customthe residue was chromatographed on silica using 7.5:92.5 methanol

Sources & evidence

ORD record: ord-18a7b469cf2b4a34ad6fa4b831586f69
Source dataset: uspto-grants-1999_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05912244

Reaction notes

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