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Updated: May 16, 2025
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Ru(II)-catalyzed oxidative C-H spiroannulation of 4-arylquinazolin-2-ones with alkynes
Chidrawar Ajay1,2, B Sridhar3,2, B V Subba Reddy1,2
1Fluoro & Agrochemicals, CSIR-Indian Institute of Chemical Technology, Hyderabad - 500007, India. basireddy@iict.res.in.
Abstract:
A novel strategy has been devised for the synthesis of spiro[indene-1,4'-quinazolin]-2'(3'H)-one frameworks through Ru(II)-catalyzed tandem ortho-C-H bond activation and spiroannulation of 4-arylquinazolin-2-ones with alkynes. This is the first example of spiroannulation of 4-arylquinazolin-2-ones with internal alkynes. It is a versatile approach for synthesizing spiro[indene-1,4'-quinazolin]-2'(3'H)-one scaffolds with a broad substrate scope and high functional group tolerance.
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