[reaction: see text] The rearrangement of the carbamoyl group in allenyl carbamate 1 in the presence of n-BuLi in situ generates the allenolate 3, which is subsequently intercepted with aromatic aldehydes furnishing (Z)- or (E)-configured Baylis-Hillman-type adducts 4 or 5. The double bond isomers can be interconverted by a retro aldol-type reaction.

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[reaction: see text] The rearrangement of the carbamoyl group in allenyl carbamate 1 in the presence of n-BuLi in situ generates the allenolate 3, which is subsequently intercepted with aromatic aldehydes furnishing (Z)- or (E)-configured Baylis-Hillman-type adducts 4 or 5. The double bond isomers can be interconverted by a retro aldol-type reaction.

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