Organic Synthesis with the Use of Silica Gel As an Effective Catalyst

使用硅胶作为有效催化剂的有机合成

• 批准号: 60550612
• 负责人: HOJO Masaru
• 金额: $ 1.41万
• 依托单位: Kobe University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60550612/
• 关键词: Silica Gel; Catalyst; Alumina; Fluorine-containing Heterocycle; Acetalization; Dithioacetalization; 2-アロイルオキシ-4-アルキル-2H-1,4-チアジン-3-オン

Silica gel, sodium sulfide supported on alumina and silica gel treated with thionyl chloride were found to have high chemoselectivity toword various organic compounds. Use of these silica gels were extended to synthesize physiologically active compounds.1. Sodium sulfide on alumina was found to be used for selective reduction of aldehydes to alcohols in the presence of ketones and also for selective reduction of nitroaldehydes to nitroalcohols.2. In the precense of silica gel ethyl <beta> -trifluoroacetylvinyl ether was found to undergo etherexchange reaction with various alcohols at the olefinic carbon atom and give many kinds of <beta> -trifluoroacetylvinyl ethers in quantitative yields.When allyl alcohol is chosen as an alcohol allyloxy group can be introduced conveniently into the system and the exchanged product, on warming for a while, underwent Claisen rearrangement to give <beta> -diketones bearing trifluoromethyl and allyl groups.These substituted <beta> -diketones reacted eff … More iciently with various bifunctional reagents such as hydrazines, hydroxylamine, urea, guanidine and so on to afford pyrazoles, isooxazoles, pyrimidines and quinolines, respectively, bearing trifluoromethyl and various substituted allyl groups. These fluorine-containing heterocycles are expected to be led to physiologically active compounds.3. It was found that silica gel treated with thionyl chloride can be served as a mild and therefore selective catalyst for acetalization and dithioacetalization. Even furfural and nicotinic aldehyde which are very sensitive toword acids are also acetalized and dithioacetalized safely with the use of this catalyst in quantitative yields.This dithioacetalization method was extended to discriminate formyl group and keto carbonyl group in an intramolecular manner. The discrimination proceeded in each case perfectly, with keto carbonyl groups remaining completely intact.4. Silica gel was found to be used for the reaction of 2-aroyloxy-4-alkyl-2h-1,4-thiazin-3-one with nucleophiles. For example, the reaction of this 2-aroyloxy compound with thiophenol and dimethylaniline in the presence of some silica gel gave sulfur-substituted and nuclei-substituted products in good yields, respectively. Less

硅胶、氧化铝负载的硫化钠和用亚硫酰氯处理的硅胶被发现对各种有机化合物具有高化学选择性。这些硅胶的用途扩展到合成生理活性化合物。 1．发现氧化铝负载的硫化钠可以在酮存在下将醛选择性还原为醇，也可以将硝基醛选择性还原为硝基醇。 2．发现乙基β-三氟乙酰乙烯基醚在硅胶存在下与各种醇在烯属碳原子上发生醚交换反应，定量生成多种β-三氟乙酰乙烯基醚。当选择烯丙醇作为醇时，可以方便地将烯丙氧基引入体系中，并且 交换产物在加热一段时间后，进行克莱森重排，得到带有三氟甲基和烯丙基的β-二酮。这些取代的β-二酮与各种双功能试剂如肼、羟胺、尿素、胍等有效反应，得到吡唑、异恶唑、 嘧啶和喹啉分别带有三氟甲基和各种取代的烯丙基。这些含氟杂环化合物有望转化为具有生理活性的化合物。 3．研究发现，用亚硫酰氯处理过的硅胶可用作缩醛化和二硫代缩醛化的温和且因此具有选择性的催化剂。即使是对酸非常敏感的糠醛和烟醛，也可以使用该催化剂以定量的产率安​​全地缩醛化和二硫代缩醛化。这种二硫代缩醛化方法扩展到以分子内方式区分甲酰基和酮羰基。每种情况下的辨别都完美地进行，酮羰基基团保持完整。4。发现硅胶可用于2-芳酰氧基-4-烷基-2h-1,4-噻嗪-3-酮与亲核试剂的反应。例如，该2-芳酰氧基化合物与苯硫酚和二甲基苯胺在一些硅胶存在下反应，分别以良好的产率得到硫取代和核取代的产物。较少的

项目成果

神鳥安啓: Chem.Lett.253-254 (1985)

上鸟泰宏：Chem.Lett.253-254 (1985)

神鳥安啓: J.Org.Chem.51. 1427-1431 (1986)

上鸟泰宏：J.Org.Chem.51（1986）。

神鳥安啓: Synthesis. 340-342 (1986)

上鸟泰宏：综合 340-342 (1986)

吉田善一 編,北條卓: "Organic Synthesis with the Use of Silica Gel as an Effective Catalyst"New Synthetic Methodology and Functionally Interesting Compounds"" KODANSHA Ltd.,Tokyo and ELSEVIER SCIENCE PUBLISHERS B.V.,Amsterdam, 20 (1986)

Zenichi Yoshida（编辑），Taku Hojo：“使用硅胶作为有效催化剂的有机合成“新合成方法和功能有趣的化合物””KODANSHA Ltd.，东京和 ELSEVIER SCIENCE PUBLISHERS B.V.，阿姆斯特丹，20 (1986)

Yasuhiro Kamitori: "A New Convenient Synthetic Method for 3-Alkyl-1, 1, 1-trifluoroacetylacetone and its Derivatives" Synthesis. 340-342 (1986)

Yasuhiro Kamitori：“一种新的便捷合成方法，用于 3-烷基-1,1,1-三氟乙酰丙酮及其衍生物”的合成。