Efficient Synthesis of Novel 3-Substituted Thiopyran-4-ones

Abstract

Synthesis of several 3-substituted thiopyran-4-ones is reported for the first time via aldol condensation of various aromatic aldehydes with dihydrothiopyran-4-one derivatives under very mild conditions using magnesium bromide diethyl etherate and triethyl­amine. The products were characterized based on spectroscopic and X-ray diffraction experiments.

Key words

thiopyrans - aldol condensation - magnesium bromide diethyl etherate - heterocycles

References

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15

The reaction is limited to aldehydes with no α-hydrogen. Under the conditions, aliphatic aldehydes undergo self condensation and the starting ketone remains intact.

16

Crystallographic data for 6c have been deposited with the Cambridge Crystallographic Data Center as supplementary publication no. CCDC-627143. Copies of these data can be obtained free of charge on application to CCDC, 12 Union Road, Cambridge CB2 1EZ, UK [Fax: [phone]; E-mail: [e-mail] or via www.ccdc.cam.ac.uk/conts/retrieving.html].