Hydrochloric Acid → 5-Chloro-2-(1-methylethyl)benzaldehyde
Reaction equation
[Mg].Br[C:3]1[CH:8]=[C:7]([Cl:9])[CH:6]=[CH:5][C:4]=1[CH:10]([CH3:12])[CH3:11].CN(C)[CH:15]=[O:16].Cl>O1CCCC1>[Cl:9][C:7]1[CH:6]=[CH:5][C:4]([CH:10]([CH3:12])[CH3:11])=[C:3]([CH:8]=1)[CH:15]=[O:16]Participants
Conditions
- Temperature
- 40 °C
Procedure
Magnesium (4.6 g, 0.189 mol) together with tetrahydrofuran (65 ml) were placed in a reaction vessel and heated while stirring to 40° C. About 5% of a solution of 2-bromo-4-chloro-1-isopropylbenzene (IV) (43 g, 0.180 mol) in tetrahydrofuran (95 ml) is then added dropwise. After the reaction has commenced, the remainder of the 2-bromo-4-chloro-1-isopropylbenzene in tetrahydrofuran was added under gentle reflux over a period of 1 hour. The mixture was then cooled to 0° C. and dimethylformamide (13.8 g. 0.189 mol) was added dropwise over a period of 1 hour. The reaction mixture obtained was stirred for another 1 hour and hydrochloric acid (86.7 g, 0.369 mol) was added in such a way that the temperature was kept below 30° C. The phases were then separated and extracted with toluene (2×50 ml). The combined organic phases were distilled under reduced pressure and the crude product obtained was recrystallized from isopropanol/water 4:1. 5-Chloro-2-isopropylbenzaldehyde (25.7 g, 99 GC-% by area, 77% of theory) was obtained as a colourless solid.
Workup
- temperatureheated
- temperatureunder gentle reflux over a period of 1 hour
- temperatureThe mixture was then cooled to 0° C.
- customThe reaction mixture obtained
- stirringwas stirred for another 1 hour
- customwas kept below 30° C
- customThe phases were then separated
- extractionextracted with toluene (2×50 ml)
- distillationThe combined organic phases were distilled under reduced pressure
- customthe crude product obtained
- customwas recrystallized from isopropanol/water 4:1
Sources & evidence
- ORD record
- ord-e70e12f848b74239a8914da176229460
- Source dataset
- uspto-grants-2016_09
- Patent number
- US09440908B2
Reaction notes
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