【结 构 式】 |
【分子编号】39937 【品名】7-(allyloxy)-5-methoxy-4-methyl-2-benzofuran-1(3H)-one 【CA登记号】 |
【 分 子 式 】C13H14O4 【 分 子 量 】234.25176 【元素组成】C 66.66% H 6.02% O 27.32% |
合成路线1
该中间体在本合成路线中的序号:(VIII)The metal-ammonia reduction of 4,6-dimethoxy-m-xylene (I) gives 1,5-dimethyl-2,4-dimethoxy-1,4-cyclohexadiene (II), which by treatment with potassium tert-butoxide in DMSO is converted into the conjugated diene (III). The Dies-Alder reaction of (III) with dimethyl acetylenedicarboxylate (A), and subsequent elimination of the bridge affords dimethyl 3-methyl-4,6-dimethoxyphthalate (IV), which is selectively monodemethylated with BCl3 yielding the o-hydroxyphthalic ester (V). The hydrolysis and anhydrization of (V) gives 3-hydroxy-5-methoxy-6-methylphthalic anhydride (VI), which is reduced with Zn and HCl in acetic acid affording 4-methyl-5-methoxy-7-hydroxyphthalide (VII). The reaction of (VII) with allyl bromide (B) by means of K2CO3 in ether gives the allylic ether (VIII), which undergoes thermal rearrangement into 4-methyl-5-methoxy-7-hydroxy-6-allyl-phthalide (IX). The ozonolysis of (IX) affords the aldehyde (X), which by a Wittig condensation with 1-formylethylydenetriphenylphosphorane (XI) is converted into the new aldehyde (XII). A new Wittig reaction of (XII) with the phosphorane (XIII) gives the ethyl ester (XIV), which is finally hydrolyzed and partially reduced with diimide.
【1】 Castaner, J.; Hillier, K.; Mycophenolic acid. Drugs Fut 1978, 3, 8, 594. |
【2】 Wright, J.J.; Birch, A.J.; A total synthesis of mycophenolic acid. J Chem Soc 1969, 14, 788-789. |
中间体序号 | 中间体编号 | 品名 | CAS号 | 分子式 | 供应商 | 用于合成 |
---|---|---|---|---|---|---|
(B) | 11463 | 3-Bromo-1-propene; 3-Bromopropene;allyl bromide | 106-95-6 | C3H5Br | 详情 | 详情 |
(A) | 24551 | Dimethyl acetylenedicarboxylate; Dimethyl 2-butynedioate;Acetylenedicarboxylic acid dimethyl ester | 762-42-5 | C6H6O4 | 详情 | 详情 |
(I) | 39930 | 1,5-dimethoxy-2,4-dimethylbenzene; 5-methoxy-2,4-dimethylphenyl methyl ether | C10H14O2 | 详情 | 详情 | |
(II) | 39931 | 1,5-dimethoxy-2,4-dimethyl-1,4-cyclohexadiene; 5-methoxy-2,4-dimethyl-1,4-cyclohexadien-1-yl methyl ether | C10H16O2 | 详情 | 详情 | |
(III) | 39932 | 3-methoxy-4,6-dimethyl-1,3-cyclohexadien-1-yl methyl ether; 2,4-dimethoxy-1,5-dimethyl-1,3-cyclohexadiene | C10H16O2 | 详情 | 详情 | |
(IV) | 39933 | dimethyl 4,6-dimethoxy-3-methylphthalate | C13H16O6 | 详情 | 详情 | |
(V) | 39934 | dimethyl 6-hydroxy-4-methoxy-3-methylphthalate | C12H14O6 | 详情 | 详情 | |
(VI) | 39935 | 7-hydroxy-5-methoxy-4-methyl-2-benzofuran-1,3-dione | C10H8O5 | 详情 | 详情 | |
(VII) | 39936 | 7-hydroxy-5-methoxy-4-methyl-2-benzofuran-1(3H)-one | C10H10O4 | 详情 | 详情 | |
(VIII) | 39937 | 7-(allyloxy)-5-methoxy-4-methyl-2-benzofuran-1(3H)-one | C13H14O4 | 详情 | 详情 | |
(IX) | 39938 | 6-allyl-7-hydroxy-5-methoxy-4-methyl-2-benzofuran-1(3H)-one | C13H14O4 | 详情 | 详情 | |
(X) | 39939 | 2-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-2-benzofuran-5-yl)acetaldehyde | C12H12O5 | 详情 | 详情 | |
(XI) | 39940 | 2-(triphenylphosphoranylidene)propanal | C21H19OP | 详情 | 详情 | |
(XII) | 39941 | (E)-4-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-2-benzofuran-5-yl)-2-methyl-2-butenal | C15H16O5 | 详情 | 详情 | |
(XIII) | 39942 | ethyl 2-(triethylphosphoranylidene)acetate | C10H21O2P | 详情 | 详情 | |
(XIV) | 39943 | ethyl (2E,4E)-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-2-benzofuran-5-yl)-4-methyl-2,4-hexadienoate | C19H22O6 | 详情 | 详情 |