Wei Hanlin, Bao Ming, Dong Kuiyong, Qiu Lihua, Wu Bing, Hu Wenhao, Xu Xinfang
Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science Soochow University, Suzhou, 215123, China.
School of Pharmaceutical Sciences Sun Yat-sen University, Guangzhou, 510006, China.
Angew Chem Int Ed Engl. 2018 Dec 21;57(52):17200-17204. doi: 10.1002/anie.201812140. Epub 2018 Nov 27.
An enantioselective Mannich-type reaction of 3-butynol and nitrones is described, which affords dihydrofuran-3-ones in good yields and with excellent enantioselectivities. The reaction is initiated by gold-catalyzed alkyne oxidation and modification of the resulting gold carbene species with a tethered hydroxy group to form enolate species; the reaction terminates with an enantioselective Mannich-type addition with the assistance of chiral phosphoric acid (CPA) and hydrogen bonding. This novel pattern of alkyne transformation involving chemical bond cleavage, and a fragment modification and reassembly process, provides an atom- and step-economic method, and is the first example of cooperative asymmetric catalysis in gold-catalyzed alkyne oxidations via an α-oxo gold carbene route.
描述了3-丁炔醇与硝酮的对映选择性曼尼希型反应，该反应能以良好的产率和优异的对映选择性得到二氢呋喃-3-酮。反应由金催化的炔烃氧化引发，并通过连接的羟基对生成的金卡宾物种进行修饰以形成烯醇化物物种；反应在手性磷酸（CPA）和氢键的协助下通过对映选择性曼尼希型加成终止。这种涉及化学键断裂、片段修饰和重新组装过程的新型炔烃转化模式提供了一种原子和步骤经济的方法，并且是通过α-氧代金卡宾途径在金催化的炔烃氧化中协同不对称催化的首个实例。
