Borane;tetrahydrofuran → (RS)-2-(4,4-dimethyl-thiochroman-6-yl)-heptanol
Reaction equation
[CH3:1][C:2]1([CH3:21])[C:11]2[C:6](=[CH:7][CH:8]=[C:9]([CH:12]([CH2:16][CH2:17][CH2:18][CH2:19][CH3:20])[C:13](O)=[O:14])[CH:10]=2)[S:5][CH2:4][CH2:3]1.B.C1COCC1>C1COCC1>[CH3:1][C:2]1([CH3:21])[C:11]2[C:6](=[CH:7][CH:8]=[C:9]([CH:12]([CH2:16][CH2:17][CH2:18][CH2:19][CH3:20])[CH2:13][OH:14])[CH:10]=2)[S:5][CH2:4][CH2:3]1Participants
Conditions
- Temperature
- 0 °C
Procedure
0.32 g of (RS)-2-(4,4-dimethyl-thiochroman-6-yl)-heptanoic acid were dissolved in 5 ml THF and treated dropwise, at 0° C., with 5.23 ml of 1M BH3.THF in THF. The mixture was stirred at 0° C. for two hours and then was quenched at 0° C. with careful addition of one portion of 5 ml of 3N HCl. The mixture was stirred at room temperature for 30 min. then was extracted with three portion of 25 ml of ethyl acetate. The combined organic extracts were dried over MgSO4 and concentrated in vacuo, giving a yellow oil. The product was purified by flash chromatography (SiO2, 10% ethyl acetate/hexanes), yielding 0.31 g of a colorless oil. 1H NMR (CDCl3): 7.10 (d, J=1.9 Hz, 1H), 6.97 (d, J=8.1 Hz, 1H), 6.81 (dd, J=8.1, 1.9 Hz, 1H), 3.65 (dd, J=10.7, 5.9 Hz, 1H), 3.57 (dd, J=10.7, 8.4 Hz, 1H), 3.00-2.90 (m, 2H), 2.65-2.55 (m, 1H), 1.95-1.85 (m, 2H), 1.65-1.35 (m, 2H), 1.26 (s, 6H), 1.25-1.05 (m, 6H), 0.87 (t, J=7.6 Hz, 3H).
Workup
- customwas quenched at 0° C. with careful addition of one portion of 5 ml of 3N HCl
- stirringThe mixture was stirred at room temperature for 30 min.
- extractionthen was extracted with three portion of 25 ml of ethyl acetate
- dry with materialThe combined organic extracts were dried over MgSO4
- concentrationconcentrated in vacuo
- customgiving a yellow oil
- customThe product was purified by flash chromatography (SiO2, 10% ethyl acetate/hexanes)
Sources & evidence
- ORD record
- ord-5339328de7cf498daf531223b8646861
- Source dataset
- uspto-grants-2003_08
- Patent number
- US06603012B2
Reaction notes
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