Synthesis of a 2,7-Dioxatricyclo[4.2.1.03,8]nonane: A Model Study for Possible Application in a Synthesis of Dictyoxetane
摘要:
A method for the synthesis of the 2,7-dioxatricyclo[4.2.1.0(3,8)]nonane ring system characteristic of the marine diterpene dictyoxetane has been developed. This method utilizes a dipolar cycloaddition of a 3-oxidopyrylium salt to create the carbon skeleton (Scheme 1) and employs an intramolecular S(N)2 displacement to form the oxetane ring (Schemes 9, 10, 13). The route described could easily be adapted to incorporate additional functionality, making it potentially useful in a total synthesis of dictyoxetane.
Synthesis of a 2,7-Dioxatricyclo[4.2.1.03,8]nonane: A Model Study for Possible Application in a Synthesis of Dictyoxetane
摘要:
A method for the synthesis of the 2,7-dioxatricyclo[4.2.1.0(3,8)]nonane ring system characteristic of the marine diterpene dictyoxetane has been developed. This method utilizes a dipolar cycloaddition of a 3-oxidopyrylium salt to create the carbon skeleton (Scheme 1) and employs an intramolecular S(N)2 displacement to form the oxetane ring (Schemes 9, 10, 13). The route described could easily be adapted to incorporate additional functionality, making it potentially useful in a total synthesis of dictyoxetane.
Lipase B from Candida antarctica catalyzes the oxidative ring expansion of furfuryl alcohols using aqueous hydrogen peroxide to yield functionalized pyranones under mild conditions. The method further allows for the preparation of corresponding piperidinone derivatives by enzymatic rearrangement of N-protected furfurylamines.
来自南极念珠菌的脂肪酶 B 使用过氧化氢水溶液催化糠醇的氧化扩环,在温和条件下产生官能化的吡喃酮。该方法还允许通过N-保护的糠胺的酶促重排来制备相应的哌啶酮衍生物。
作者:Daniel Thiel、Fabian Blume、Christina Jäger、Jan Deska
DOI:10.1002/ejoc.201800333
日期:2018.6.7
HUOM! TAMA MANUSKA ON TILASSA CLOSED KUNNES ARTIKKELI ON JULKAISTU JA JULKAISUVIIVE MAARITELTY KUSTANTAJAN JULKAISUPAIVASTA ALKAEN. The manuscript is "closed" until the article has been published and the embargo date can be defined.
呼!蒂拉萨岛上的 TAMA MANUSKA 关闭了 JULKAISTU JA JULKAISUVIIVE MAARITELTY KUSTANTAJAN JULKAISUPAIVASTA ALKAEN 的 KUNNES ARTIKKELI。在文章发表并且可以确定禁运日期之前,手稿处于“关闭”状态。
Selective Functionalization of Achmatowicz Rearrangement Products by Reactions with Potassium Organotrifluoroborates under Transition-Metal-Free Conditions
作者:Silvia Roscales、Víctor Ortega、Aurelio G. Csákÿ
DOI:10.1021/acs.joc.8b01643
日期:2018.9.21
The repertoire of synthetic transformations of the products of the Achmatowiczrearrangement has been expanded by exploring their reactivity with potassium organotrifluoroborates in the absence of transition metals. Depending on the reaction conditions and the substitution pattern of the starting material, the reaction may lead to the stereoselective synthesis of dihydropyranones (2,6-trans), tetrahydropyranones
A novel, environment-friendly method to prepare pyranones from furfural alcohols <i>via</i> photocatalytic O<sub>2</sub> oxidation in an aqueous phase
作者:Bei Zhou、Yun-Feng Tao、Yu-Juan He、Lan-Xiang Liu、Zu-Hui Chang、Xiang-Hong Li、Tong Lin、Guan-Ben Du
DOI:10.1039/d2gc03344e
日期:——
This study developed a novel photocatalytic method to synthesize pyranones from furfural alcohols. By using 0.2 mol% equivalent of tris-Ir(ppy)3 as a photocatalyst under visible light and O2 as the reaction atmosphere, furfural alcohols were rapidly oxidized and hydrolyzed in the aqueous reaction solution to produce diol intermediates, which further underwent hydrolysis, furan ring-opening and rearrangement