Hydrochloric Acid → 3-(4-Propyl-phenyl)-propionaldehyde dimethylacetal
Reaction equation
[CH2:1]([C:4]1[CH:9]=[CH:8][C:7]([CH2:10][CH2:11][CH:12]=[O:13])=[CH:6][CH:5]=1)[CH2:2][CH3:3].C[C@H](NC([C@H]1N(C([C@@H](NC([C@@H](N)CC2C=CC(O)=CC=2)=O)CC(O)=O)=O)CCC1)=O)[C:16](N1[C@H](C(N2[C@H](C(N3[C@H](C(N4[C@H](C(N5[C@H](C(N6[C@H](C(O)=O)CCC6)=O)CCC5)=O)CCC4)=O)CCC3)=O)CCC2)=O)CCC1)=[O:17].Cl.[CH3:90]O>>[CH3:90][O:13][CH:12]([O:17][CH3:16])[CH2:11][CH2:10][C:7]1[CH:8]=[CH:9][C:4]([CH2:1][CH2:2][CH3:3])=[CH:5][CH:6]=1Participants
Conditions
- Temperature
- 0 °C
Procedure
A reaction flask was charged with 3-(4-propyl-phenyl)-propionaldehyde (147 g, prepared as above), methanol (500 mL), and TMOF (90 g). The reaction mass was cooled to 0° C. and hydrochloric acid (37%, 1 g) was added in one portion. The reaction was exothermic and the temperature rose to 23° C. The reaction mass was quenched with sodium methoxide in methanol (25%, 10 g) and the solvent was removed by evaporation. The crude intermediate product 3-(4-propyl-phenyl)-propionaldehyde dimethylacetal was provided and confirmed by the NMR analysis. 3-(4-Propyl-phenyl)-propionaldehyde dimethylacetal was further treated with phosphoric acid (10 g) and pyridine (8 g) at 200° C. The reaction mass was aged for 4 hours, during which methanol was recovered in a Dean Stark trap. The reaction mass was then cooled and washed with aqueous sodium carbonate solution. Fractional distillation of the organic layer afforded the product 4-propyl 1-(3-methoxy-2-propen-1-yl)benzene (80 g), which had a boiling point of 101° C. at a pressure of 3 mmHg.
Workup
- customrose to 23° C
- customThe reaction mass was quenched with sodium methoxide in methanol (25%, 10 g)
- customthe solvent was removed by evaporation
Sources & evidence
- ORD record
- ord-25fc8c8139334247aa0940b0783b4526
- Source dataset
- uspto-grants-2012_05
- Patent number
- US08168834B2
Reaction notes
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