Asymmetric synthesis and synthetic utility of 2,3-dihydro-4-pyridones
Asymmetric synthesis and synthetic utility of 2,3-dihydro-4-pyridones
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DOI：
10.1002/jhet.5570360610
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发表时间：
1999-11-01
影响因子：
2.4
通讯作者：
Comins, DL
中科院分区：
文献类型：
--
作者：
Comins, DL
95%。通过重结晶或色谱纯化得到主要非对映异构体，为空气稳定的白色固体。在大多数情况下，需要除去并回收手性助剂，裂解三异丙基甲硅烷基，并将氮重新保护为氨基甲酸酯。典型的序列如图4所示。通过三个合成步骤由吡啶4以高产率制备对映体纯二氢吡啶酮结构单元7。杂环 7 是二氢吡啶酮结构单元的一个很好的例子，因为它在 C-2 侧链以及环中含有有用的官能团。
95%. Purification by recrystallization or chromatography gives the major diastereomer as an air stable white solid. In most cases, it is desireable to remove and recover the chiral auxiliary, cleave the triisopropylsilyl group, and reprotect the nitrogen as a carbamate. A typical sequence is depicted in Scheme 4. The enantiopure dihydropyridone building block 7 is prepared in high yield from pyridine 4 in three synthetic steps. The heterocycle 7 is a good example of a dihydropyridone building block for it contains useful functionality in the C-2 side-chain as well as in the ring.