17538-94-2Relevant academic research and scientific papers
Silver-Catalyzed Cyclopropanation of Alkenes Using N-Nosylhydrazones as Diazo Surrogates
Liu, Zhaohong,Zhang, Xinyu,Zanoni, Giuseppe,Bi, Xihe
, p. 6646 - 6649 (2017)
An efficient silver-catalyzed [2 + 1] cyclopropanation of sterically hindered internal alkenes with diazo compounds in which room-temperature-decomposable N-nosylhydrazones are used as diazo surrogates is reported. The unexpected unique catalytic activity of silver was ascribed to its dual role as a Lewis acid activating alkene substrates and as a transition metal forming silver carbenoids. A wide range of internal alkenes, including challenging diarylethenes, were suitable for this protocol, thereby affording a variety of cyclopropanes with high efficiency in a stereoselective manner under mild conditions.
Enantioselective Cyclobutenylation of Olefins Using N-Sulfonyl-1,2,3-Triazoles as Vicinal Dicarbene Equivalents
Burns, Noah Z.,Mercer, Jaron A. M.,Patel, Sajan C.,Smith, Myles W.,Suzuki, Kensuke
supporting information, p. 6530 - 6535 (2021/09/02)
Cyclobutenes are highly useful synthetic intermediates as well as important motifs in bioactive small molecules. Herein, we report a regio-, chemo-, and enantioselective synthesis of cyclobutenes from olefins using N-sulfonyl-1,2,3-triazoles as vicinal dicarbene equivalents or alkyne [2 + 2] cycloaddition surrogates. Terminal and cis-olefins can be transformed into enantioenriched cyclopropanes via rhodium catalysis. Then, in one pot, treatment of these intermediates with tosyl hydrazide and base effects diazo formation followed by rhodium-catalyzed ring expansion to yield enantioenriched cyclobutenes. These cyclobutenes can be transformed into highly substituted, enantioenriched cyclobutanes, including structures relevant to natural product scaffolds.
Iron-catalyzed synthesis of cyclopropanes by in situ generation and decomposition of electronically diversified diazo compounds
Allouche, Emmanuelle M. D.,Al-Saleh, Afnan,Charette, André B.
supporting information, p. 13256 - 13259 (2018/12/11)
The modular synthesis of a variety of trans 1,2-disubstituted cyclopropanes in a safe and user-friendly one-pot iron-catalyzed cyclopropanation reaction is described. Easily synthesized N-nosylhydrazones are used as diazo precursors, allowing the in situ generation of electron-rich diazo compounds under mild reaction conditions and their direct participation in the cyclopropanation reaction.
Improved zinc-catalyzed simmons-smith reaction: Access to various 1,2,3-trisubstituted cyclopropanes
Levesque, Eric,Goudreau, Sebastien R.,Charette, Andre B.
, p. 1490 - 1493 (2014/04/03)
The Simmons-Smith reaction of zinc carbenoids with alkenes is a powerful method to access cyclopropanes containing various substitution patterns. This work exploits the high reactivity of aryldiazomethanes toward zinc halides to generate aryl-substituted carbenoids catalytically. These carbenoids are able to cyclopropanate various alkenes diastereoselectively, including unfunctionalized substrates such as styrenes. The zinc catalyst can be modified to tolerate the use of free allylic alcohols.
Cyclopropanation with gold(I) carbenes by retro-Buchner reaction from cycloheptatrienes
Solorio-Alvarado, César R.,Wang, Yahui,Echavarren, Antonio M.
, p. 11952 - 11955 (2011/10/04)
Cationic gold(I) promotes the retro-Buchner reaction of 7-substituted 1,3,5-cycloheptatrienes, leading to gold(I) carbenes that cyclopropanate alkenes.
