Can enamines be formed from α,β-unsaturated ketones? This question was a result of discussion form here: α,β-unsaturated carbonyl compounds and alkyl addition

The reaction below (condensation of cyclohexenone with a secondary amine) does not yield any results on a literature search, even when I only search for the product by itself (unless my search was not good enough):



Can enamines actually be formed from α,β-unsaturated ketones? If not, what prevents it from being possible?
Stork and Birnbaum have reported (Tetrahedron Lett. 1961, 10, 313) the formation of dienamine 2 from octalone 1. Alkylation with methyl iodide leads to α-alkylation of the dienamine. Buffer conditions are required for hydrolysis of the dienamine to octalone 4.