The thermal1,3-dipolarcycloadditions of 4-acetoxyallenoates 1 with various dipoles have been reported. When azomethine imines and nitrones are used as the 1,3-dipole partner, the corresponding reactions afford 2,3-dihydropyrazole and 2,3-dihydroisoxazole derivatives, respectively. These reactions might proceed via a thermal1,3-dipolarcycloaddition and the subsequent elimination of HOAc. In addition
Phosphine-catalyzed dearomatizing [3+2] annulations of isoquinolinium methylides with allenes
作者:Zhi-Jun Jia、Constantin Gabriel Daniliuc、Andrey P. Antonchick、Herbert Waldmann
DOI:10.1039/c4cc08555h
日期:——
A phosphine-catalyzed annulation provides an access to highly functionalized pyrroloisoquinolines with high regioselectivity.
一种膦催化的环化反应提供了一种高区域选择性的高度官能化的吡咯异喹啉的合成方法。
Highly Enantioselective Synthesis of [1,2,4]Triazino[5,4-<i>a</i>]isoquinoline Derivatives via (3 + 3) Cycloaddition Reactions of Diazo Compounds and Isoquinolinium Methylides
An array of chiral [1,2,4]triazino[5,4-a]isoquinoline derivatives were obtained in excellent yields (up to 98%) and with excellent enantioselectivities (up to 99% ee) via a new highly asymmetric (3 + 3) cycloaddition reaction of diazocompounds and isoquinolinium methylides, with a bifunctional chiral phase-transfer catalyst (PTC). Density functional theory calculations show that PTC has a bridge role
Transition metal-free annulative vinylene transfer <i>via</i> the 1,3-dipolar reaction of <i>N</i>-ylides: access to benzo-fused indolizines
作者:Limin Zhao、Wen Li、Jiali Liu、Linying Ni、Zhihao Liu、Hao Shen、Hua Cao、Xiang Liu
DOI:10.1039/d2ob01846b
日期:——
efficient metal-free annulative vinylene transfer protocol for the synthesis of benzo-fused indolizines via 1,3-dipolar cycloadditions of N-ylides with vinylene carbonate has been developed. Vinylene carbonate serves as an acetylene surrogate without any external oxidant involved. This transformation leads to the direct construction of versatile benzo-fused indolizine derivatives in moderate to good yields
Synthesis of Fluorinated Pyrrolo[2,1-<i>a</i>]isoquinolines through Decarboxylative/Dehydrofluorinative [3 + 2] Cycloaddition Aromatization of Isoquinolinium <i>N</i>-Ylides with Difluoroenoxysilanes
作者:Wenxue Xi、Yiheng Zhang、Haijian Wu、Jinshan Li、Yurong Wang、Jianguo Yang、Zhiming Wang、Weijun Yao
DOI:10.1021/acs.orglett.3c01728
日期:2023.7.7
isoquinolinium N-ylides with difluoroenoxysilanes has been developed. This methodology provides a facile and straightforward synthetic pathway to afford highly functionalized fluorinated pyrrolo[2,1-a]isoquinolines in good to excellent yields under mild conditions. Moreover, gram-scale and synthetic derivatization experiments for the late-stage functionalization of drug molecules have also been demonstrated
开发了异喹啉鎓N-叶立德与二氟烯氧基硅烷的脱羧/脱氟化氢形式[3+2]环加成芳构化反应。该方法提供了一种简便易行的合成途径,可在温和条件下以良好至优异的产率提供高度官能化的氟化吡咯并[2,1- a ]异喹啉。此外,还论证了药物分子后期功能化的克级和合成衍生化实验。