Article
Chemistry, Physical
Wenbin Liu, Jack Twilton, Bo Wei, Maizie Lee, Melissa N. Hopkins, John Bacsa, Shannon S. Stahl, Huw M. L. Davies
Summary: A mild method for accessing diazo compounds via aerobic oxidation of hydrazones was described, using a Cu(OAc)(2)/pyridine catalyst and molecular oxygen. Insight gained from mechanistic studies led to the expansion of this method to include diaryl hydrazones, delivering diaryl diazomethane derivatives. The products can be used in rhodium carbene catalysis without isolation of the diazo intermediate to afford cyclopropane products in good yield with high enantioselectivity.
Article
Chemistry, Multidisciplinary
Ricardo Labes, Julio C. Pastre, Richard J. Ingham, Claudio Battilocchio, Henrique M. Marcon, Mariana C. F. C. B. Damiao, Duc N. Tran, Steven V. Ley
Summary: This study reports the rapid synthesis of 2-pyrazolines from aldehydes via [3 + 2] cycloaddition of unstabilised diazo species and mono and di-substituted alkenes. The development includes semi-continuous and fully continuous methods, with a fully automated compound library generation and a graphical interface for automation control.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Shengjie Jiang, Yanping Cai, Thayalan Rajeshkumar, Iker del Rosal, Laurent Maron, Xin Xu
Summary: This work presents the synthesis, characterization, and reactivity of the first well-defined zinc α-diazoalkyl complex. The complex reacts with a nickel catalyst to form an α-zincated phosphorus ylide, or undergoes [3+2] cycloaddition with CO2 or CO to produce a five-membered heterocyclic product. The use of CO in the cycloaddition reaction is unprecedented, demonstrating a novel CO reaction mode.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Sudeshna Mondal, Chandan Kumar Giri, Mahiuddin Baidya
Summary: The weakly coordinating enaminone functionality is essential for the ruthenium-catalyzed C-H bond activation strategy, enabling the regioselective coupling of arenes with diazonaphthoquinones to produce polycyclic benzocoumarins in high yields. The protocol operates through a Ru(II)/Ru(IV) catalytic pathway and allows for the diversification of various pharmacophore-coupled substrates.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Yangjinxiu Zhou, Tengfei Pang, Yu Liu, Fangrui Zhong, Guojiao Wu
Summary: We present a highly intriguing and underexplored multi-component reaction involving diazo molecules for polyene formation. This reaction involves coupling of 2,2,2-trifluorodiazoethane and aryl alkynes mediated by iodine under visible light. The reaction provides a straightforward and step-economic access to bistrifluoromethylated 1,3,5-trienes in high stereoselectivity by creating three C=C bonds in a single step under mild conditions.
Article
Chemistry, Organic
Nour Tanbouza, Virginie Carreras, Thierry Ollevier
Summary: Efficient synthesis of 3-trifluoromethyl-3-aryl-cyclopropenes was achieved via the cyclopropenation reaction of alkynes with photolytically generated carbenes from diazirine compounds. The reaction was conducted in continuous flow using readily available LEDs under mild reaction conditions, resulting in yields up to 97% for 25 examples. Control experiments showed that diazirines are more efficient than diazo compounds for this transformation.
Article
Chemistry, Organic
Yu-Ting Tian, Fa-Guang Zhang, Jun-An Ma
Summary: A novel Et3N-catalyzed [3 + 2] cycloaddition reaction has been developed for the synthesis of various pyrazoles from allenoates by reacting with acceptor diazo compounds. 3-Alkynoates can also participate in the reaction by isomerizing to allenoates in situ.
Review
Chemistry, Organic
Rajnish Kumar, Himanshu Singh, Avijit Mazumder, Salahuddin, Ranjeet Kumar Yadav
Summary: The pyrazoline moiety is widely used in pharmaceutical, agricultural, and industrial sectors, and its chemistry has been extensively studied. Various synthesis strategies have been developed, but researchers are continuously exploring greener and more economical methods.
CURRENT ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yong-Liang Su, Kuiyong Dong, Haifeng Zheng, Michael P. Doyle
Summary: A new catalytic methodology for synthesizing pyrazolines from alpha-diazo compounds and conjugated alkenes was reported. The regiocontrolled addition of diazomethyl radicals to carbon-carbon double bonds followed by intramolecular ring closure and tautomerization achieved a diverse set of pyrazolines in good yields with excellent regioselectivity. This strategy overcomes the limitations of electron-deficient alkenes and opens new opportunities for versatile transformations of diazo compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Xinyu Zhang, Jinli Zhang, Jie Chen, Banghua Zhou, Jian Zhang, Shunhong Chen, Jian Wu, Yaojia Jiang
Summary: An efficient and straightforward synthetic method for constructing trifluoromethyl 2H-thiophenes through [4 + 1] cycloaddition of enaminothiones with trifluoromethyl N-tosylhydrazones has been disclosed. The cycloaddition platforms were found to be compatible with a broad substrate scope and to show high regio- and stereo-selectivities under very mild reaction conditions such as room temperature, neutral media and low loading of catalyst.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Sourav Roy, Apurba Biswas, Hrishikesh Paul, S. k Ariyan, Indranil Chatterjee
Summary: A rare example of visible-light-mediated diverse reactivity of N-sulfinylamines with different types of carbene precursors has been discovered. This method allows for the synthesis of valuable amides and alpha-iminoesters, without the use of transition metals or coupling reagents, by utilizing acylsilanes, aryldiazoacetates, and diazocarbonyls as carbene precursors. The use of visible light as a key promoter makes this method easily accessible.
Article
Chemistry, Multidisciplinary
Nicholas J. Porter, Emma Danelius, Tamir Gonen, Frances H. Arnold
Summary: This study developed a catalyst that uses diazirines as carbene precursors, providing a new strategy for selective carbene transfer. By engineering variants of ApePgb protoglobin, selective carbene transfer from diazirines can be achieved at room temperature. The structure of an ApePgb variant, determined by microcrystal electron diffraction, revealed how evolution has enhanced access to the heme active site for this new-to-nature catalysis.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Shreedhar Devkota, Sonaimuthu Mohandoss, Yong Rok Lee
Summary: An efficient and facile In(iii)-catalyzed reaction of 3-diazoindolin-2-ones with different arylhydrazines is demonstrated, providing a rapid synthetic route to diversely functionalized 3-arylhydrazonoindolin-2-ones in good yields. This novel method introduces biologically and photo-functionally interesting hydrazones at the 3-position of indolin-2-ones.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Martin Linden, Silja Hofmann, Antonia Herman, Nicole Ehler, Robin M. M. Baer, Siegfried R. R. Waldvogel
Summary: This study presents the first electrochemical approach for the direct synthesis of pyrazolines and pyrazoles from easily accessible hydrazones and dipolarophiles. The method allows for large-scale production and even conversion of highly sensitive alkenes. The use of a biphasic system with sodium iodide as a supporting electrolyte and mediator is cost-effective. Mechanistic insight is provided by the isolation of key intermediates, and the synthesis of a commercial herbicide safener further highlights the significance of this reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Durga Prasad Hari, Guillaume Pisella, Matthew D. Wodrich, Artem Tsymbal, Farzaneh Fadaei Tirani, Rosario Scopelliti, Jerome Waser
Summary: A new oxyalkynylation/cycloaddition reaction has been reported to synthesize complex polycyclic structures under mild conditions, with high efficiency and atom economy. The obtained products can be applied as chiral ligands for metal catalysis, providing a new method for organic synthesis. Computational studies provided a first rationalization of the low activation energy for the cycloaddition reaction based on counter-intuitive favorable dispersive interactions in the transition state.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Susanna T. S. Chan, Michael A. Pullar, Iman M. Khalil, Emmanuelle Allouche, David Barker, Brent R. Copp
TETRAHEDRON LETTERS
(2015)
Review
Chemistry, Organic
Emmanuelle M. D. Allouche, Andre B. Charette
SYNTHESIS-STUTTGART
(2019)
Review
Chemistry, Multidisciplinary
Emmanuelle M. D. Allouche, Elija Grinhagena, Jerome Waser
Summary: Hypervalent iodine compounds are powerful reagents for biomolecule functionalization, with recent advances in peptide and protein modification up to June 2021. Their use as group transfer or oxidizing reagents targeting polar, aromatic, or aliphatic amino acids and peptide termini is discussed in this Minireview.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Emmanuelle M. D. Allouche, Raphael Simonet-Davin, Jerome Waser
Summary: A methodology for C-H azidation of N-terminal proline-containing peptides using commercially available reagents was developed. Peptides containing multiple amino acids were selectively azidated at the carbamate-protected N-terminal residue, while maintaining other functional groups. Post-functionalizations of the obtained compounds via cycloaddition reactions or C-C bond formations were achieved, providing easy access to diversified peptides.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Emmanuelle M. D. Allouche, Andre B. Charette
Article
Chemistry, Multidisciplinary
Emmanuelle M. D. Allouche, Sylvain Taillemaud, Andre B. Charette
CHEMICAL COMMUNICATIONS
(2017)
Article
Chemistry, Multidisciplinary
Emmanuelle M. D. Allouche, Afnan Al-Saleh, Andre B. Charette
CHEMICAL COMMUNICATIONS
(2018)
