Regiocontrolled Synthesis of Ring-Fused Thieno[2,3-c]pyrazoles through 1,3-Dipolar Cycloaddition of Nitrile Imines with Sulfur-Based Acetylenes
作者:Jay Zumbar Chandanshive、Bianca Flavia Bonini、Denis Gentili、Mariafrancesca Fochi、Luca Bernardi、Mauro Comes Franchini
DOI:10.1002/ejoc.201001048
日期:2010.11
1,3-Dipolarcycloadditions of C-carboxymethyl-N-arylnitrile imines with substituted acetylenes bearing thiol or sulfone groups were studied. The sulfur controls the regiochemistry of the reaction, and this protocol was applied to the synthesis of ring-fused thieno[2,3-c]pyrazoles.
Synthesis and Characterization of Oxadisilole-Fused 1<i>H</i>-Benzo[<i>f</i>]indazoles and 1<i>H</i>-Naphtho[2,3-<i>f</i>]indazoles
作者:Yajuan Zhang、Xuyan Ma、Yali Chen、Xuanming Chen、Lei Guo、Weiguo Cao、Jie Chen、Man Shing Wong
DOI:10.1002/ejoc.201300110
日期:2013.5
1H-benzo[f]- and 1H-naphtho[2,3-f]indazoles have been synthesized by the 1,3-dipolar cycloaddition reactions of benzo- or naphtho-oxabicycloalkenes with nitrile imines generated in situ from N-arylhydrazonoyl chlorides followed by deoxygenation and aromatization. The photophysical, redox and thermal properties of these compounds have been characterized. Some of the indazoles show potential as deep-blue emitters
1,3-Dipolar Cycloaddition of Nitrile Imines with Cyclic α-β-Unsaturated Ketones: A Regiochemical Route to Ring-Fused Pyrazoles
作者:Jay Zumbar Chandanshive、Bianca Flavia Bonini、William Tiznado、Carlos A. Escobar、Julio Caballero、Cristina Femoni、Mariafrancesca Fochi、Mauro Comes Franchini
DOI:10.1002/ejoc.201100558
日期:2011.7.8
1,3-Dipolarcycloadditions of C-carboxymethyl-N-arylnitrile imines with cyclic α,β-unsaturated ketones of various sizes have been studied. After cycloaddition, oxidative aromatization gives the ring-fusedpyrazoles. Computational studies and the use of topological analyses of the Fukui functions allows a theoretical description of the local reactivity that is in agreement with the experimentally observed
One-flask synthesis of 1,3,5-trisubstituted 1,2,4-triazoles from nitriles and hydrazonoyl chlorides via 1,3-dipolar cycloaddition.
一瓶法合成1,3,5-三取代-1,2,4-三唑,从腈和叠氮酰氯通过1,3-偶极环加成。
Uncommon aqueous media for nitrilimine cycloadditions. I. Synthetic and mechanistic aspects in the formation of 1-aryl-5-substituted-4,5-dihydropyrazoles
作者:Giorgio Molteni、Alessandro Ponti、Marco Orlandi
DOI:10.1039/b205063c
日期:2002.9.23
A number of 1-aryl-5-substituted-4,5-dihydropyrazoles 4 have been synthesised by 1,3-dipolar cycloaddition of variously substituted nitrilimines 2 onto the appropriate alkenyl dipolarophiles 3 in aqueous media and in the presence of a surfactant. Under these conditions, uncommon for the large majority of [3 + 2] cycloadditions, the electronic features of both the cycloaddends strongly dictate the reaction outcome. Clean and fast cycloadditions were observed between electron-rich nitrilimines and electron-poor dipolarophiles, while the reversal of the electronic features of the reactants gave poor results. Changes in surfactant concentration leads to some novel mechanistic insights.