Azomethine ylides generated from the reaction of chromone-3-carbaldehyde with α-amino acids undergo 1, 5-electrocyclization reactions to afford 3-and 4-(2-hydroxybenzoyl) pyrroles. These ylides can be trapped with dipolarophiles in 1, 3-dipolar cycloaddition reactions to yield chromonyl pyrrolidines. The reaction of chromone-3-carbaldehyde with methyl glycinate gives a mixture of pyrrole, pyridine, and 3-aza-9-xanthenone derivatives.
