Photochemistry of Aminoketones. XV. Photochemical Acyl Migration in N-Tosyl-β-aminovinyl-phenyl-ketones N-Tosyl-β-aminovinyl-phenyl-ketones 1a – i are prepared in good yields from β-chlorovinyl- phenyl-ketones by reaction with the sodium salts of tosyl amides in dry DMF at room temperature. In contrast to the relatively photostable N, N-dialkyl-β-aminovinyl-aryl-ketones the electronically excited 1 give irreversible chemical reactions within a few minutes. Among other not identified photoproducts the α-tosyl-β-aminovinyl-phenyl-ketones 2 were found. From the experimental results it is evident that the migration of the tosyl group prefers a radical-type two step reaction through an intermediate X/Y of a (1,5)-NO-tosylrearrangement.
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