2-Chlorobenzoxazole → 4-(Benzoxazol-2-yl)benzyl alcohol
Reaction equation
C([Li])CCC.Br[C:7]1[CH:14]=[CH:13][C:10]([CH2:11][OH:12])=[CH:9][CH:8]=1.Cl[C:16]1[O:17][C:18]2[CH:24]=[CH:23][CH:22]=[CH:21][C:19]=2[N:20]=1>C1COCC1>[O:17]1[C:18]2[CH:24]=[CH:23][CH:22]=[CH:21][C:19]=2[N:20]=[C:16]1[C:7]1[CH:14]=[CH:13][C:10]([CH2:11][OH:12])=[CH:9][CH:8]=1Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- -78 °C
Procedure
To 500 ml THF cooled to -78° C. is added butyl lithium (2 eq.) followed by 4-bromobenzyl alcohol (27.2 g; 145 mmol) slowly over 45 minutes in a solution of THF (100 ml) keeping the temperature below -72° C. After 10 minutes following the final addition of the alcohol is added 2-chlorobenzoxazole (23.3 g; 145 mmol) in 25 ml THF slowly over 45 minutes. The temperature is maintained at -78° C. for 1 hour and then warmed to -40° C. for 15 minutes. The reaction is then quenched with 15 ml of acetic acid and allowed to warm to room temperature, diluted with 800 ml ether, washed 3× with H2O and brine, dried (MgSO4) and concentrated in vacuo to obtain a brown oily solid which is washed with 400 ml petroleum ether and filtered to obtain 4-(benzoxazol-2 -yl)benzyl alcohol as a tan solid which is used directly in Step D.
Workup
- customthe temperature below -72° C
- temperaturewarmed to -40° C. for 15 minutes
- customThe reaction is then quenched with 15 ml of acetic acid
- temperatureto warm to room temperature
- additiondiluted with 800 ml ether
- washwashed 3× with H2O and brine
- dry with materialdried (MgSO4)
- concentrationconcentrated in vacuo
- customto obtain a brown oily solid which
- washis washed with 400 ml petroleum ether
- filtrationfiltered
Sources & evidence
- ORD record
- ord-3fc3aa6aafa648a8aa97ad58694996a8
- Source dataset
- uspto-grants-1995_03
- Patent number
- US05395846
Reaction notes
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