Use of a "Structural Dummy" α-Silyl Substituent in Nazarov Cyclization: Expanding the Substrate Scope to Indanones
Hyerim Kim1, Jeongyeon Hwang1, Gwanwoo Baek2
1Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea.
Abstract:
Aryl vinyl ketones, particularly those lacking an α-substituent, are among the most challenging substrates for Nazarov cyclization. We present a practical method to expand the scope of this reaction, enabling the efficient synthesis of indanones and bicyclic 2-pyrones. The use of an α-silyl substituent as a "structural dummy" enhances reactivity, and thus, the reaction proceeds under mild conditions. Notably, spontaneous desilylation during the reaction leaves the products with double-enolizable α-hydrogens, offering greater flexibility for functionalization at the α-position of the ketone.
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