438564-92-2Relevant academic research and scientific papers
Cs2CO3 Catalyzed Intramolecular Aminocarbonylation of Alkynes: Synthesis of 3-Amino-1H-inden-1-ones from N-tert-Butyl-2-(1-alkynyl)benzaldimines
Guo, Zhen,Liu, Tao,Liang, Xiujuan,Wu, Yuting,Yao, Tuanli
supporting information, p. 1053 - 1057 (2020/02/11)
Synthesis of a wide variety of 3-amino-1H-inden-1-ones from N-tert-butyl-2-(1-alkynyl)benzaldimines via intramolecular aminocarbonylation of alkynes using Cs2CO3 as catalyst and air as oxidant has been developed. This highly atom-efficient, transition-metal-free reaction proceeds under thermal conditions. We propose that the reaction proceeds through an unprecedented 5-exo-dig cyclization of N-tert-butyl-2-(1-alkynyl)benzaldimines and thermal rearrangement of 3-methylene-2λ2-isoindolin-1-ols. (Figure presented.).
Synthesis of substituted isoquinolines via iminoalkyne cyclization using Ag(i) exchanged K10-montmorillonite clay as a reusable catalyst
Jeganathan, Mariappan,Pitchumani, Kasi
, p. 38491 - 38497 (2014/11/08)
Monosubstituted isoquinolines are synthesized in good to excellent yields by the Ag(i)-exchanged K10-montmorillonite clay catalyzed ring closure of iminoalkynes. This silver catalyzed ring closure is highly effective in cyclizing aryl- and alkyl-substituted iminoalkynes at 100 °C and accommodates a variety of iminoalkynes, thus affording a convenient route to the synthesis of isoquinolines. The other salient features of this procedure are its reusability, environmentally benign nature, high yield, operational simplicity with fewer steps, easy separation, and minimization of metallic wastes. The reaction proceeds smoothly in moderate yields and tolerates various functional groups. The solid catalyst can be readily recovered and reused. Notably, no additional base or other co-catalysts are needed. A plausible mechanism is proposed in which isoquinolines are formed via simultaneous bifunctional acid-base catalysis by Ag(i) clay. the Partner Organisations 2014.
Synthesis of substituted isoquinolines via iminoalkyne cyclization using Ag(i) exchanged K10-montmorillonite clay as a reusable catalyst
Jeganathan, Mariappan,Pitchumani, Kasi
, p. 38491 - 38497 (2014/12/11)
Monosubstituted isoquinolines are synthesized in good to excellent yields by the Ag(i)-exchanged K10-montmorillonite clay catalyzed ring closure of iminoalkynes. This silver catalyzed ring closure is highly effective in cyclizing aryl- and alkyl-substituted iminoalkynes at 100 °C and accommodates a variety of iminoalkynes, thus affording a convenient route to the synthesis of isoquinolines. The other salient features of this procedure are its reusability, environmentally benign nature, high yield, operational simplicity with fewer steps, easy separation, and minimization of metallic wastes. The reaction proceeds smoothly in moderate yields and tolerates various functional groups. The solid catalyst can be readily recovered and reused. Notably, no additional base or other co-catalysts are needed. A plausible mechanism is proposed in which isoquinolines are formed via simultaneous bifunctional acid-base catalysis by Ag(i) clay. This journal is
Competition studies in alkyne electrophilic cyclization reactions
Mehta, Saurabh,Waldo, Jesse P.,Larock, Richard C.
scheme or table, p. 1141 - 1147 (2009/07/11)
The relative reactivity of various functional groups toward alkyne electrophilic cyclization reactions has been studied. The required diarylalkynes have been prepared by consecutive Sonogashira reactions of appropriately substituted aryl halides and competitive cyclizations have been performed using I2, ICl, NBS and PhSeCl as electrophiles. The results indicate that the nucleophilicity of the competing functional groups, polarization of the alkyne triple bond, and the cationic nature of the intermediate are the most important factors in determining the outcome of these reactions.
Synthesis of 4-(1-alkenyl)isoquinolines by palladium(II)-catalyzed cyclization/olefination
Huang, Qinhua,Larock, Richard C.
, p. 980 - 988 (2007/10/03)
A variety of 4-(1-alkenyl)-3-arylisoquinolines have been prepared in moderate to excellent yields by the Pd(II)-catalyzed cyclization of 2-(1-alkynyl)arylaldimines in the presence of various alkenes. The introduction of an o-methoxy group on the arylaldimine promotes the Pd-catalyzed cyclization and stabilizes the resulting Pd(II) intermediate, improving the yields of the isoquinoline products. Ketone-containing isoquinolines 36 and 49-51 have also been prepared by this process when unsaturated alcohols are employed as the alkenes.
