Acetaldehyde → Ethyl 3-(1-propenyl)benzoate
반응식
[Br-].[CH3:2][O:3][C:4]([C:6]1[CH:7]=[C:8]([CH:29]=[CH:30][CH:31]=1)[CH2:9][P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)=[O:5].[O-][CH2:33][CH3:34].[Na+].[CH:36](=O)C>>[CH:9]([C:8]1[CH:7]=[C:6]([CH:31]=[CH:30][CH:29]=1)[C:4]([O:3][CH2:2][CH3:36])=[O:5])=[CH:33][CH3:34]참가 물질
실험 절차
The preparation of begins with the known methyl 3-(bromomethyl)benzoate. This halide is heated in xylene solution with triphenylphosphine to yield (3-methoxycarbonylbenzyl)triphenylphosphonium bromide. The phosphonium salt is converted to the ylide with sodium ethoxide and the ylide caused to react with acetaldehyde to yield ethyl 3-(1-propenyl)benzoate. (Note that the ethyl ester has been obtained as a result of transesterification with solvent ethanol.) The ester is heated with N-bromosuccinimide in carbon tetrachloride for an extended period to yield ethyl 3-(3-bromo-1-propenyl)benzoate. This compound is treated with the anion derived from methyl methylthiomethyl sulfoxide as described in section (b) above. The resulting dimethylmercaptal S-oxide is hydrolyzed with acid catalysis to ethyl 3-(4-oxo-1-butenyl)benzoate. Hydrogenation of this olefinic aldehyde over a palladium catalyst affords the aldehyde intermediate XXIII.
출처 및 근거
- ORD 기록
- ord-0788509c82434a748da8ac7bd9f2071b
- 출처 데이터셋
- uspto-grants-1980_09
- 특허 번호
- US04225609
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