【结 构 式】 |
【分子编号】39944 【品名】(E)-3-methyl-3-penten-2-one 【CA登记号】565-62-8 |
【 分 子 式 】C6H10O 【 分 子 量 】98.1448 【元素组成】C 73.43% H 10.27% O 16.3% |
合成路线1
该中间体在本合成路线中的序号:(XVI)The condensation of diethyl malonate (XV) with 3-methylpent-3-en-2-one (XVI) by means of sodium ethoxide in ethanol gives 5,6-dimethyl-4-ethoxycarbonylcyclohexane-1,3-dione (XVII), which is aromatized to 5,6-dimethyl-4-ethoxycarbonylresorcinol (XIX) by treatment with FeCl3 in refluxing acetic acid, or by bromination to 2-bromo-5,6-dimethyl-4-ethoxycarbonylresorcinol and debromination with H2 over Pd/C. The methylation of (XIX) with diazomethane or methyl iodide and K2CO3 gives the corresponding dimethyl ether (XX), which is hydrolyzed with NaOH affording 2,4-dimethoxy-5,6-dimethylbenzoic acid (XXI). This acid by reaction with SOCl2 gives the acyl chloride (XXII), which by reaction with NH3 is converted into the amide (XXIII). The reaction of (XXIII) with tert-butyl hypochlorite affords the N-chloroamide (XXIV), which is photolyzed to the intermediate iminolactone (XXV) and immediately hydrolyzed to 4-methyl-5,7-dimethoxyphthalide (XXVI).
【1】 Canonica, L.; et al.; Total synthesis of mycophenolic acid. Tetrahedron Lett 1971, 28, 2691-92. |
【2】 Castaner, J.; Hillier, K.; Mycophenolic acid. Drugs Fut 1978, 3, 8, 594. |
中间体序号 | 中间体编号 | 品名 | CAS号 | 分子式 | 供应商 | 用于合成 |
---|---|---|---|---|---|---|
(XV) | 16825 | 2-[4-(tert-butoxy)-5-fluoro-3-methyl-2-pyridinyl]-2-cyclopropylacetonitrile | C15H19FN2O | 详情 | 详情 | |
(XVI) | 39944 | (E)-3-methyl-3-penten-2-one | 565-62-8 | C6H10O | 详情 | 详情 |
(XVII) | 39945 | ethyl 2,3-dimethyl-4,6-dioxocyclohexanecarboxylate | C11H16O4 | 详情 | 详情 | |
(XVIII) | 39946 | ethyl 3-bromo-2,4-dihydroxy-5,6-dimethylbenzoate | C11H13BrO4 | 详情 | 详情 | |
(XIX) | 39947 | ethyl 4,6-dihydroxy-2,3-dimethylbenzoate | C11H14O4 | 详情 | 详情 | |
(XX) | 39948 | ethyl 4,6-dimethoxy-2,3-dimethylbenzoate | C13H18O4 | 详情 | 详情 | |
(XXI) | 39949 | 4,6-dimethoxy-2,3-dimethylbenzoic acid | C11H14O4 | 详情 | 详情 | |
(XXII) | 39950 | 4,6-dimethoxy-2,3-dimethylbenzoyl chloride | C11H13ClO3 | 详情 | 详情 | |
(XXIII) | 39951 | 4,6-dimethoxy-2,3-dimethylbenzamide | C11H15NO3 | 详情 | 详情 | |
(XXIV) | 39952 | N-chloro-4,6-dimethoxy-2,3-dimethylbenzamide | C11H14ClNO3 | 详情 | 详情 | |
(XXV) | 39953 | 5,7-dimethoxy-4-methyl-2-benzofuran-1(3H)-imine | C11H13NO3 | 详情 | 详情 | |
(XXVI) | 39954 | 5,7-dimethoxy-4-methyl-2-benzofuran-1(3H)-one | C11H12O4 | 详情 | 详情 |