从乙烯基碳酸乙烯酯和双磺酰甲烷开始,已经完成了一种用于合成高度官能化的环戊烯醇的有效的一锅法。该协议通过顺序钯催化脱羧烯丙基化和氧化环化以操作简单的方式进行。广泛的底物可以很好地适应各种环戊烯醇,以中等至良好的产率和优异的选择性。进一步的对照实验表明,可分离的 ( Z )-烯丙醇(高达Z / E = >19:1)的选择性形成是后续级联氧化环化成功的基础。
A One-Pot Stereoselective Synthesis of Electron-Deficient 4-Substituted (E,E)-1-Arylsulfonylbuta-1,3-dienes and Their Chemoselective [3+2] Cycloaddition with Azomethine Ylides - A Simple Synthesis of 1,3,4-Trisubstituted Pyrrolidines and Pyrroles
A simple and efficient method for the synthesis of ( E , E )-1-(arylsulfonyl)buta-1,3-dienes bearing electron-withdrawing substituents like cyano and ethoxycarbonyl at position 4, involving a one-pot alkylation of bis(phenylsulfonyl)methane with trans -ethyl 4-bromocrotonate/ trans -4-bromocrotononitrile, and elimination of arylsulfinic acid, is described. These dienes undergo facile mono [3+2] cycloaddition
一种简单有效的合成 ( E , E )-1-(芳基磺酰基)buta-1,3-二烯的方法,该方法在 4 位带有吸电子取代基,如氰基和乙氧基羰基,包括双(苯磺酰基)的一锅烷基化) 甲烷与反式-4-溴巴豆酸乙酯/反式-4-溴巴豆腈,以及芳基亚磺酸的消除。这些二烯通过偶氮甲碱叶立德化学选择性进行简单的单 [3+2] 环加成,以提供功能化的 1,3,4-三取代吡咯烷。在温和条件下用MnO 2 ·SiO 2 氧化这些环加合物提供1,3,4-三取代的吡咯。
Methylene-Bridged Dimerization by Cu-Catalyzed Deconstructive C–C Cleavage of Oxacycloalkane
作者:Xu Yuan、Jimei Yang、Xingjiang Yang、Na He、Mingyuan Han、Jun Lin、Wei Yu、Xiaohong Cheng、Yi Jin
DOI:10.1021/acs.orglett.3c02015
日期:2023.8.4
Herein, we demonstrate the successful utilization of copper catalysis and oxygenoxidation for consecutive C(sp3)–C(sp3) bond cleavage in alkyl cyclic ethers. A key step involves a copper–oxygen autoxidation process, generating in situ alkoxy radicals and triggering sequential C–C bond cleavage. This β-oxidative cleavage strategy enables the use of cyclic ethers as valuable C1 building blocks for the synthesis
Alkylative Lactonization of g,d-Unsaturated Esters with a-Chloro Sulfides. A Concise Synthesis of the Monoterpene Lactone from Chrysanthemum flosculosum L.
作者:Hiroyuki Ishibashi、Hiroshi Nakatani、Taru Su So、Toyokazu Fujita、Masazumi Ikeda
DOI:10.3987/com-89-5258
日期:——
TAMURA, YASUMITSU;ANNOURA, HIROKAZU;FUJI, MASAHIRO;OKURA, MASAMI;ISHIBASH+, CHEM. AND PHARM. BULL., 1986, 34, N 2, 540-549