Zirconium oxide (NP) - ionic liquid as an efficient media for the domino Knoevenagel hetero Diels-Alder reaction with unactivated alkynes
作者:Saeed Balalaie、Ali Poursaeed、Malihe Javan Khoshkholgh、Hamid Reza Bijanzadeh、Eckardt Wolf
DOI:10.1016/j.crci.2011.12.002
日期:2012.4
Immobilized ZrO 2 -nanopowder (NP) in ionic liquid and different organic solvents was used as a suitable Lewis-acid for the synthesis of polycyclic heterocycles which contains pyran-based skeletons. Reaction of O -propargylated salicylaldehyde with activemethylenecompounds in the presence of ZrO 2 -NP in ionic liquid proceeds via domino Knoevenagel hetero Diels-Alder reaction of unactivated alkynes
Pyridinium triflate catalyzed intramolecular alkyne-carbonyl metathesis reaction of O-propargylated 2-hydroxyarylaldehydes
作者:Manoj Kumar Saini、Harshita Singh Korawat、Shashi Kant Verma、Ashok K. Basak
DOI:10.1016/j.tetlet.2020.152657
日期:2020.12
3,5-Dibromopridinium trifluoromethanesulfonate catalyzes the intramolecular alkyne-carbonyl metathesis reaction of a variety of O-propargylated 2-hydroxyarylaldehydes and ketonesbearingalkyl, aryl and heteroaryl substituted internal alkynes to provide various 3-(hetero)aroyl 2H-chromenes in high yields.
A new and efficient CuI-catalyzed dominoKnoevenagel hetero-Diels-Alderreaction of 1-oxa-1,3-butadienes with terminal unactivated acetylenesas building blocks to afford pyrano[2,3- C]pyrazoleshas been developed. The products were obtained in good to high yieldsin most cases. Synthesis of polycyclic compounds in one-pot, witheasy workup, and mild reaction conditions are advantages of ourreported method
一种新型高效的 CuI 催化 1-oxa-1,3-丁二烯与末端未活化乙炔的多米诺 Knoevenagel 异-Diels-Alder 反应作为构建单元得到吡喃并 [2,3-C] 吡唑。在大多数情况下以良好到高产率获得产物。一锅法合成多环化合物、后处理容易、反应条件温和是我们报道的方法的优点。
Gold-catalyzed formation of aryl-fused pyrazolooxazepines <i>via</i> intramolecular regioselective <i>7-exo-dig</i> cyclization
作者:Ravinder Guduru、N. S. V. M. Rao Mangina、Balasubramanian Sridhar、Galla V. Karunakar
DOI:10.1039/c8ob03157f
日期:——
synthesis of substituted aryl-fused pyrazolooxazepines from ortho-O-propargyl aryl pyrazoles by gold catalysis. In this organic transformation a new C–N bond was formed regioselectively via 7-exo-dig cyclization. Moderate to good yields of aryl-fused pyrazolooxazepine derivatives were obtained with significant molecular complexity in one-pot.
Synthesis of 1H,7H,12bH-Pyrano[3′,4′: 5,6]pyrano[3,4-c][1]benzopyran-1-one via Domino Knoevenagel/Hetero-DielsAlder Reaction with Theoretical Investigations
intramolecular oxa‐DielsAlder reaction of 2‐(prop‐2‐yn‐1‐yloxy)benzaldehydes as unactivated terminal alkynes with 4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one is described. The reaction proceeds with remarkable chemoselectivity to yield pyranones 3 (Scheme 1). A theoretical investigation of the reaction in terms of HOMOLUMO interactions in the gas phase is also reported. The reaction could be regarded as an in
描述了CuI催化的分子内oxa Diels - Al 2-(prop-2-yn-1-yloxy)苯甲醛作为未活化的末端炔烃与4-hydroxy-6-methyl-2 H -pyran-2-one的Alder反应。反应以显着的化学选择性进行,得到吡喃酮3(方案1)。反应在HOMO方面的理论探讨还报道在气相中LUMO的相互作用。该反应可以被认为是逆电子点播狄尔斯阿尔德环加成。理论结果与实验证据高度吻合。