Enantioselective synthesis of naphthopyran derivatives catalyzed by bifunctional thiourea-tertiary amines
摘要:
An efficient bifunctional thiourea catalyzed addition-cyclization reaction of 2-naphthol with alpha,alpha-dicyanoolefins is realized under mild conditions to afford the corresponding naphthopyran derivatives in high yields and moderate enantioselectivities. Additionally, the development of an asymmetric three-component one-pot procedure for the synthesis of naphthopyran derivatives is also reported. (c) 2008 Elsevier Ltd. All rights reserved.
Enantioselective synthesis of 3‐amino‐1‐aryl‐1<i>H</i>‐benzo[<i>f</i>]chromene‐2‐carbonitrile derivatives by Fe<sub>3</sub>O<sub>4</sub>@PS‐arginine as an efficient chiral magnetic nanocatalyst
for one‐pot enantioselectivesynthesis of 3‐amino‐1‐aryl‐1H‐benzo[f]chromene‐2‐carbonitrile derivatives. The results showed that in the presence of 0.07 g Fe3O4@PS‐Arg nanocatalyst and ethanol as solvent, the best reaction yield (96%) was obtained in the least time (5 min). Easy operation, reusability and stability, short reaction time, high reaction yields and good enantioselectivity are the major
通过用氯丙基硅烷对Fe 3 O 4磁性纳米颗粒(MNPs)进行表面改性,再通过精氨酸形成Fe 3 O 4 @丙基硅烷-精氨酸(Fe 3 O 4 @ PS-Arg),制备了一种新型手性磁性纳米催化剂。在通过傅立叶变换红外,X射线衍射,场发射扫描电子显微镜,透射电子显微镜,振动样品磁法和热重分析确定了Fe 3 O 4 @ PS‐Arg合成的MNPs的结构后,对其催化活性进行了评估。一锅对映选择性合成3-氨基-1-芳基-1 H-苯并[ f] chromene-2-碳腈衍生物。结果表明,在0.07 g Fe 3 O 4 @ PS-Arg纳米催化剂和乙醇作为溶剂的存在下,最短反应时间(5分钟)可获得最佳反应收率(96%)。易于操作,可重复使用和稳定,反应时间短,反应产率高和对映选择性好是新合成的纳米催化剂的主要优点。同样,该研究为进一步研究和研究新型可重复使用的对映选择性催化剂和手性化合物的合成提供了新的策略。
Enantioselective synthesis of naphthopyran derivatives catalyzed by bifunctional thiourea-tertiary amines
作者:Xiao-Sheng Wang、Gao-Sheng Yang、Gang Zhao
DOI:10.1016/j.tetasy.2008.02.018
日期:2008.4
An efficient bifunctional thiourea catalyzed addition-cyclization reaction of 2-naphthol with alpha,alpha-dicyanoolefins is realized under mild conditions to afford the corresponding naphthopyran derivatives in high yields and moderate enantioselectivities. Additionally, the development of an asymmetric three-component one-pot procedure for the synthesis of naphthopyran derivatives is also reported. (c) 2008 Elsevier Ltd. All rights reserved.