A highly enantioselective synthesis of 3, 4-diaminochroman-2-ones has been realized via the domino reaction of o-hydroxy aromatic aldimines and azlactones. Notably, a cis-product was obtained as the major product by the use of guanidine 2a whereas a trans-product was the major product with bisguanidium salt 3• HBArF4. In two cases, various substituted 3, 4- dihydrocoumarins were obtained with high yields (up to 99%) as well as excellent ...