Catalyst free 1,3-dipolar cycloaddition of 3-oxo-1,2-pyrazolidinium ylides to β-trifluoroacetyl vinyl ethyl ether: Synthesis of 6-trifluoroacetyl substituted bicyclic pyrazolidinones

A catalyst free cycloaddition reaction of 3-oxo-1,2-pyrazolidinium ylides with β-trifluoroacetyl vinyl ethyl ether is reported, which proceeded smoothly at ambient temperature and afford the bicyclic pyrazolidinone products in good yield. This is the first report of synthesis of 6-trifluoroacetyl substituted bicyclic pyrazolidinones that are potentially anti-microbial and herbicidal.