Synthesis ofα-Siloxyamides by the Reaction of a Carbamoylsilane with Ketones

Abstract

Under using anhydrous toluene as a solvent, N,N-dimethyl carbamoyl(trimethyl)silane reacted with a series of aryl ketones or unsaturated aryl ketones at 105 ℃ to afford α-siloxyamide derivatives in good yields (60%～89%). The structures of the products were characterized by element analysis, 1 H NMR, 13 C NMR and IR spectra. The alkyl ketones including the alkyl-aryl ketones and alkyl-unsaturated ketones poorly reacted with N,N-dimethylcarbamoyl(trimethyl)silane. The experimental results showed that the electronic property of the substituted group on the aryl ring strongly affected the reaction. In the case of the aryl ketones with stronger donor group on the aryl ring, the longer time was needed for the reaction.

Synthesis of 3-Hydroxy-3-heterocyclebutylamide Derivatives Using Carbamoylsilanes as an Amide Source

“…硅烷难与四元或五元环酮以及在羰基的 α-位含有 sp 3 杂 化碳原子的酮反应, 并常常被酮的 α-活泼氢水解成甲酰 胺 [20] . 最近在研究药物的合成过程中, 我们尝试用氨甲 酰基硅烷与四元杂环丁酮反应, 反应能够顺利进行.…”

“…在与醛的反应中 发现 [21] , 醛的位阻小、反应快, 氨甲酰基硅烷能与脂肪 醛反应, 不被 α-活泼氢水解. 在与酮的反应中发现 [20] , 反应较慢, 一般需要几天才能完成, 芳香酮、不饱和芳 酮能反应, 脂肪酮、四元或五元环酮难反应, 即使羰基 只有一端连有脂肪基也不能反应, 并且氨甲酰基硅烷常 被 α-活泼氢水解, 说明 α-活泼氢对氨甲酰基硅烷的水解 反应与加成反应是竞争性反应. 由于酮的位阻大, 反应 慢导致了 α-活泼氢的水解成主反应.…”

Selective Addition of Carbamoylsilane to Vicinal Diketones: Highly Efficient Synthesis of β-Keto-α-hydroxyamides

“…However, in our previous studies, ketones possessing sp 3 -carbon on the α-position of the carbonyl group could not react with carbamoylsilane 1 in most cases. 6 The result may be due to the electron-withdrawing effect of adjacent carbonyl group. The reaction proceeds slow as compared to that of the benzyl 2a under the same conditions.…”

“…We have recently addressed in other contexts by using carbamoylsilanes to convert carbonyl compounds directly into α-hydroxy-amides. 6 However, the scope of this protocol is limited to the reaction of aryl ketones and aryl-unsaturated ketones. To further explore the addition reaction of carbamoylsilane with C=O group of ketones, we tested vicinal diketones, and now found that the addition reaction of the carbamoylsilanes with various vicinal diketones could directly afford good yields of β-keto-α-siloxyamides, and the reaction is of selectivity between two carbonyl groups.…”

Synthesis of α-Alkoxycarbonyl-α-siloxyamides by the Reaction of a Carbamoylsilane with α-Ketoesters

“…近年来, 有机硅试剂作为碳基源合成羰基化合物的反应 研究有了较快进展, 如用 α-三甲基硅基乙酸酯与醛的加 成反应制备 β-羟基酯的研究 [21] , 用腈基三甲基硅与 α,β 不饱和酮反应合成 β-腈基酮的研究 [22～24] 等. 本课题组 开展了用氨甲酰基硅烷在底物分子中引入氨酰基的反 应研究, 实现了氨酰基直接引入到亚胺 [25 ～ 27] 、醛和 酮 [28,29] 、芳烃和酰卤 [30,31] 的分子中, 一步合成了 α-氨基 酰胺、α-羟基酰胺、酰胺和 α-羰基酰胺, 于是我们想探 索用氨甲酰基硅烷来合成 α-羟基-α-烷氧羰基酰胺的方 法. 研究发现用 α-羰基酯作起始原料, 通过与氨甲酰基 硅烷的加成反应, 能方便高效地合成 α-羟基-α-烷氧羰 基酰胺, 部分结果已以快报形式报道 [32] , 本文将全文详 细介绍这一研究工作, 同时报道立体选择性合成 α-羟 基-α-烷氧羰基酰胺的尝试结果.…”