Synthesis and Chemical Shifts Calculation of a-Acyloxycarboxamides Derived from Indane-l,2,3-trione by DFT and HF Methods

α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were confirmed by IR, 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. The B3LYP/HF calculations for computation of 1H and 13C NMR chemical shifts have been carried out for the title compounds at the 6-311+G** and 6-311++G** basis set levels within GIAO and CSGT approaches. Predicted 1H and 13C NMR che-mical shifts have been assigned and compared with experimental 1H and 13C NMR spectra and they are supported each other.