Lithium aluminum hydride → (8-Bromo-4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulen-2-yl)-methanol
Reaction equation
[AlH4-].[Li+].[Br:3][C:4]1[CH:20]=[CH:19][C:7]2[C:8]3[N:9]=[C:10]([C:16](O)=[O:17])[S:11][C:12]=3[CH2:13][CH2:14][O:15][C:6]=2[CH:5]=1>O1CCCC1>[Br:3][C:4]1[CH:20]=[CH:19][C:7]2[C:8]3[N:9]=[C:10]([CH2:16][OH:17])[S:11][C:12]=3[CH2:13][CH2:14][O:15][C:6]=2[CH:5]=1Participants
Conditions
- Temperature
- 0 °C
Procedure
Lithium tetrahydroaluminate (0.363 g, 9.56 mmol) was suspended in tetrahydrofuran (30 mL) and cooled to 0° C. A solution of 8-Bromo-4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulene-2-carboxylic acid (1.04 g, 3.19 mmol) in tetrahydrofuran (1 mL) was then added dropwise over a 10 min period. The resulting reaction mixture was stirred while warming to r.t. for 12 h. LCMS indicated that the reaction was completely converted with a minor uncharacterized impurity present (<5%). The reaction was quenched by diluting with saturated Rochelle's salt solution and EtOAc (1:1, 200 mL). The mixture was stirred very vigorously until the phases separated. The layers were then partitioned and the aqueous layer was extracted with EtOAc (3×). The combined organic portions were dried over MgSO4, filtered and concentrated. The crude residue was purified by ISCO chromatography (40 g column, 0-75% EtOAc/heptane) to provide 0.63 g (63% yield) of (8-Bromo-4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulen-2-yl)-methanol. LC/MS (ESI+): m/z 313.2 (M+H).
Workup
- customThe resulting reaction mixture
- temperaturewhile warming to r.t. for 12 h
- customThe reaction was quenched
- additionby diluting with saturated Rochelle's salt solution and EtOAc (1:1, 200 mL)
- stirringThe mixture was stirred very vigorously until the phases
- customseparated
- customThe layers were then partitioned
- extractionthe aqueous layer was extracted with EtOAc (3×)
- dry with materialThe combined organic portions were dried over MgSO4
- filtrationfiltered
- concentrationconcentrated
- customThe crude residue was purified by ISCO chromatography (40 g column, 0-75% EtOAc/heptane)
Sources & evidence
- ORD record
- ord-ae0ac185ffce4add99c3de1f90a3f2cc
- Source dataset
- uspto-grants-2014_03
- Patent number
- US08673952B2
Reaction notes
Loading…