{"title":"3-Amino Oxindole Schiff Base 与对醌甲酰胺高效配对,在金鸡纳铵相转移催化剂作用下实现新的非对映选择性和对映体选择性 1,6-Conjugated Addition","authors":"","doi":"10.1016/j.tetlet.2024.155262","DOIUrl":null,"url":null,"abstract":"<div><p>3‑Amino oxindole Schiff base has been used as an efficient substrate company with <em>p</em>‑quinone methides for a new highly diastereoselective and enantioselective 1,6-conjugate addition in the presence of a O-allyl-N-(9-anthracenylmethyl) cinchonidinium bromide phase transfer catalyst under mild reaction conditions. A broad series of chiral quaternary 3-amino oxindoles with 4-hydroxybenzyl scaffold were smoothly obtained in good to excellent yields with excellent diastereoselectivities (>20:1) and enantioselectivities (up to 99 % ee). A typical scale-up preparation and subsequent hydrolysis of a pyridine substrate was successfully performed and a potential valuable chiral amino-pyridine bifunctional chiral building block was obtained, which is structurally feasible as chiral ligand for asymmetric metallic catalysis.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5000,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"3‑Amino Oxindole Schiff Base Efficiently Paired with p‑Quinone Methide to Enable a New Diastereoselective and Enantioselective 1,6-Conjugated Addition in the Presence of a Cinchonidinium Phase Transfer Catalyst\",\"authors\":\"\",\"doi\":\"10.1016/j.tetlet.2024.155262\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>3‑Amino oxindole Schiff base has been used as an efficient substrate company with <em>p</em>‑quinone methides for a new highly diastereoselective and enantioselective 1,6-conjugate addition in the presence of a O-allyl-N-(9-anthracenylmethyl) cinchonidinium bromide phase transfer catalyst under mild reaction conditions. A broad series of chiral quaternary 3-amino oxindoles with 4-hydroxybenzyl scaffold were smoothly obtained in good to excellent yields with excellent diastereoselectivities (>20:1) and enantioselectivities (up to 99 % ee). A typical scale-up preparation and subsequent hydrolysis of a pyridine substrate was successfully performed and a potential valuable chiral amino-pyridine bifunctional chiral building block was obtained, which is structurally feasible as chiral ligand for asymmetric metallic catalysis.</p></div>\",\"PeriodicalId\":438,\"journal\":{\"name\":\"Tetrahedron Letters\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.5000,\"publicationDate\":\"2024-08-20\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Tetrahedron Letters\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0040403924003575\",\"RegionNum\":4,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, ORGANIC\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Tetrahedron Letters","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0040403924003575","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, ORGANIC","Score":null,"Total":0}
3‑Amino Oxindole Schiff Base Efficiently Paired with p‑Quinone Methide to Enable a New Diastereoselective and Enantioselective 1,6-Conjugated Addition in the Presence of a Cinchonidinium Phase Transfer Catalyst
3‑Amino oxindole Schiff base has been used as an efficient substrate company with p‑quinone methides for a new highly diastereoselective and enantioselective 1,6-conjugate addition in the presence of a O-allyl-N-(9-anthracenylmethyl) cinchonidinium bromide phase transfer catalyst under mild reaction conditions. A broad series of chiral quaternary 3-amino oxindoles with 4-hydroxybenzyl scaffold were smoothly obtained in good to excellent yields with excellent diastereoselectivities (>20:1) and enantioselectivities (up to 99 % ee). A typical scale-up preparation and subsequent hydrolysis of a pyridine substrate was successfully performed and a potential valuable chiral amino-pyridine bifunctional chiral building block was obtained, which is structurally feasible as chiral ligand for asymmetric metallic catalysis.
期刊介绍:
Tetrahedron Letters provides maximum dissemination of outstanding developments in organic chemistry. The journal is published weekly and covers developments in techniques, structures, methods and conclusions in experimental and theoretical organic chemistry. Rapid publication of timely and significant research results enables researchers from all over the world to transmit quickly their new contributions to large, international audiences.