A stereoselective, tandem [2+2] photocycloaddition–hydrolysis route to aldol-type adducts

Abstract

Photocycloadditions of aromatic aldehydes 2a–e with cyclic ketene silyl acetals 1a–e have been investigated. Regio- and exo-selective formation of the bicyclic 2-alkoxyoxetanes 3 was observed in high yields. Hydrolysis of the acid-labile oxetanes 3 with neutral water was efficiently achieved to give aldol-type adducts 4 (threo-selective formations).

References

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