Fused-Ring Heterocycle Syntheses From Thiazole, Oxazole, Benzoxazole, And Benzothiazole Derivatives And Trifluoroacetylations Of N-Methyl Cyclic Ketene-N,O/S-Acetals. Attempted Syntheses Of Functionalized Polymers From Plant-Derived 5-(Hydroxymethyl)Furfural