The 1 H NMR spectra and the IR carbonyl stretching frequencies of methyl (3-, 4-, and 5- substituted 2-thiophenecarboxylate) s have been reported. Good linear correlations between the chemical shifts of the ring protons in methyl (4-and 5-substituted 2- thiophenecarboxylate) s and those of the corresponding protons in substituted thiophenes were observed. The coupling constants in methyl (substituted 2-thiophenecarboxylate) s ...
