壹、利用乙基二苯膦 (EtPPh2) 催化醛類、丙烯酸酯類和丙二酸二乙酯的三組分反應 貳、帶有芳香官能基及氰基取代呋喃之合成方法開發
Abstract
本論文分為兩部分，第一部分主要是以EtPPh2催化醛類、丙烯酸酯類和丙二酸二乙酯23a進行三組分反應，此反應在一步同時生成兩個新的碳-碳鍵。推測的反應機構是經由Morita-Baylis-Hillman反應，接著親核試劑進行Michael加成至Morita-Baylis-Hillman產物上。藉由改變催化劑種類、溶劑、催化劑劑量數、當量數及更換不同取代基探討不同條件對於反應性的影響，篩選出最佳化條件後，在室溫下反應4到21小時後可以得到具有高度官能基之化合物之三組分反應產物，其產率介於50%~63%之間。
第二部分是合成四取代呋喃化合物，以帶有氰基的烯酮類42、三正丁基膦、醯氯46以及三乙基胺當鹼製備具有多芳香官能基及一個氰基的呋喃，反應時間為10分鐘到4小時，產率高達84~99%，為極其有效率的製備方法；反應機構推測是由三正丁基膦與化合物42進行Michael 加成後的產物在與46進行acylation ，接著去質子化形成中間體44，最後在進行分子內Wittig 反應而得呋喃分子。
The dissertation is divided into two parts. The first part focuses on the EtPPh2 catalyzed three-component reactions of aldehyde, alkyl acrylate and dialkyl malonate in which two new carbon-carbon bonds form in one step. The reaction is proposed to proceed via the Morita-Baylis-Hillman reaction followed by the Michael addition of nucleophilic reagents toward the Morita-Baylis-Hillman adduct. The screening of reaction condition (types of catalysts, solvent, amount of reactants) were carefully examined. Under our optimized reaction condition, numerous highly functionalized compounds bearing the hydroxy group and ester functionality can be easily prepared at room temperature within 4 - 21 h in moderate yields (39~63%). The second part decribes the preparation of tetrasubstituted furans, bearing three aryl groups and a cyano group, starting from the Michael acceptor 42, tributylphosphine, and acyl chlorides 46. All the corresponding furans can be generated in one step at room temperature within 10 min to 4 h in high yields (84~99%). The reaction mechanism is proposed to undergo the Michael reaction of PBu3 toward 42 followed by acylation with 46, deprotonation of the corresponding intermediate 44, and an intramolecular Wittig reaction of 47.
The dissertation is divided into two parts. The first part focuses on the EtPPh2 catalyzed three-component reactions of aldehyde, alkyl acrylate and dialkyl malonate in which two new carbon-carbon bonds form in one step. The reaction is proposed to proceed via the Morita-Baylis-Hillman reaction followed by the Michael addition of nucleophilic reagents toward the Morita-Baylis-Hillman adduct. The screening of reaction condition (types of catalysts, solvent, amount of reactants) were carefully examined. Under our optimized reaction condition, numerous highly functionalized compounds bearing the hydroxy group and ester functionality can be easily prepared at room temperature within 4 - 21 h in moderate yields (39~63%). The second part decribes the preparation of tetrasubstituted furans, bearing three aryl groups and a cyano group, starting from the Michael acceptor 42, tributylphosphine, and acyl chlorides 46. All the corresponding furans can be generated in one step at room temperature within 10 min to 4 h in high yields (84~99%). The reaction mechanism is proposed to undergo the Michael reaction of PBu3 toward 42 followed by acylation with 46, deprotonation of the corresponding intermediate 44, and an intramolecular Wittig reaction of 47.
Description
Keywords
呋喃, 三組分反應, 乙基二苯膦, furan, three-component reactions