Orchestrated Triple CH Activation Reactions Using Two Directing Groups: Rapid Assembly of Complex Pyrazoles1. (16th January 2015)

• Record Type: Journal Article
• Authors: Yang, Weibo; Ye, Shengqing; Fanning, Dewey; Coon, Timothy; Schmidt, Yvonne; Krenitsky, Paul; Stamos, Dean; Yu, Jin‐Quan
• Is Part Of: Angewandte Chemie. Volume 127:Number 8(2015)
• Page Start: 2531
• Page End: 2534
• Publication Date: 2015-01-16
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201410462
• Languages: English
• ISSNs: 0044-8249

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A sequential triple CH activation reaction directed by a pyrazole and an amide group leads to the well‐controlled construction of sterically congested dihydrobenzo[e]indazole derivatives. This cascade reaction demonstrates that the often problematic competing CH activation pathways in the presence of multiple directing groups can be harvested by design to improve step economy in synthesis. Pyrazole as a relatively weak coordinating group is shown to direct C<inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh3thgc7cx" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:00448249:media:ANGE201410462:tex2gif-inf-1" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext> </mml:mtext><mml:mrow><mml:mtext>sp</mml:mtext><mml:msup><mml:mtext> </mml:mtext><mml:mrow><mml:mtext>3</mml:mtext></mml:mrow></mml:msup></mml:mrow></mml:msub></mml:math></alternatives></inline-formula>H activation for the first time.</p> </abstract>