7-溴-4,4-二甲基-1-四氢萘酮 → 3-溴苯乙醛

HRID 1355

反应方程式

HRID 1355 反应方程式
BrC1C=C2C(C(C)(C)CCC2=O)=CC=1.[Br:15][C:16]1[CH:17]=[C:18]([CH2:22][C:23](OCC)=[O:24])[CH:19]=[CH:20][CH:21]=1.[H-].C([Al+]CC(C)C)C(C)C>>[Br:15][C:16]1[CH:17]=[C:18]([CH2:22][CH:23]=[O:24])[CH:19]=[CH:20][CH:21]=1

参与物

4

实验过程

Compound G can be obtained as described in J. Med. Chem. 1995, 38, 4764-4767, and as shown in Reaction Scheme 1. Thus, referring now specifically to Reaction Scheme 1, ethyl 3-bromophenylacetate (Compound B, made by esterification of 3-bromophenylacetic acid) is reduced with diisobutylaluminum hydride (DIBAL H) to yield (3-bromophenyl)acetaldehyde. (3-Bromophenyl)acetaldehyde is reacted in a Wittig reaction with (carbethoxymethylene)triphenylphosphorane to provide a mixture of E and Z ethyl 4-(3-bromophenyl)but-2-enoates. The latter compounds are hydrogenated to yield ethyl 4-(3-bromophenyl)butanoate (Compound D). Compound D is reacted with the Grignard reagent derived from methylbromide to give the tertiary alcohol 5-(3-bromophenyl)-2-methylpentan-2-ol (Compound E) (It should be apparent to those skilled in the art, that the choice of the Grignard reagent used in this reaction step determines the nature of the R1 substituent in the resulting compounds of the invention.) Compound E is then treated with acid to cyclize it and to form 6-bromo-1,2,3,4-tetrahydro-1,1-dimethylnaphthalene (Compound F). Compound F is oxidized with chromium trioxide to yield 7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound G). The isomeric compound, 6-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound H) can be obtained, starting with ethyl (4-bromophenyl)acetate, in accordance with the sequence of reactions illustrated in Reaction Scheme 1 for Compound G.

后处理

  1. custom1995, 38, 4764-4767, and as shown in Reaction Scheme 1

来源与证据

ORD记录
ord-a12f514f3a754a2d8e08fdd22d30526b
来源数据集
uspto-grants-1998_03
专利号
US05723666

关联笔记

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