Novel Synthesis of <alpha>-Amino Ketones Using the Characterristics of Sulfur Compounds

在目前的项目中，一种新颖的方法被用于合成N-单-替代<Alph>的氨基酮（1）是医学和农业化学品的有用合成中介。研究方法包括三个过程： （一）将胺添加到酮二硫代乙酸S和S-二氧化物中（2）添加一个添加剂; （二）将其消耗的添加剂的烷基化（3）;和（三）将亚序酸羟基化引向一个氨基酮（1）。我们发现了一种初级胺不可逆地添加到2个添加到一个添加剂（3）在一个好的年薪中<alph>。在0 ° C的DMF中，NaH的烷基碘化物与房间温度的反应中， 3个包含了计算产品（4），是被提交给没有任何隔离的亚序羟基的。对于4个羟基，在较高浓度的羟基酸的使用中发现了一种临界的平滑羟基。然后，再冲洗（2-4 h）在1：4中混合物中的碳酸氢酸和甲醇获得了最好的结果。然后，我们建立了一种方便的方法来制备<alpha>-氨基酮（1）。

In the present project, a novel method was established for synthesizing N-mono-substituted <Alph>-amino ketones (1) which are useful synthetic intermediates of medicines and agricultural chemicals. The investigated method comprizes three processes: (i) the addition of an amine to a ketene dithioacetal S,S-dioxide (2) to give an adduct; (ii) alkylation of the thus-obtained adduct (3); and iii) the subsequent acidhydroxylsis leading to an <alph>-amino ketone (1).We have found that a primary amine irreversibly adds to 2 to afford the adduct (3) in a good yield. In the reaction with an alkyl iodide in the presence of NaH in DMF at 0 ゜C to room temperature, 3 afforded a Calkylation product (4), which was subjected to the subsequent hydrolysis without any isolation. For hydrolysis of 4, employment of the higher concentration of hydrochloric acid was found to be crucial to smooth hydrolysis. Thus, refluxing (2-4 h) of the slution of crude 4 in a 1:4 mixture of conc hydrochloric acid and methanol gave the best result.Thus we established a convenient method for the preparation of <alpha>-amino ketones (1).