A one-pot multicomponent reaction of 2-carboxy-benzaldehyde, nitrile/aniline and a nucleophile (N, N- disubstituted aniline) generated a variety of functionalized N-substituted isoindolinone derivatives. The metal-free intramolecular cyclization reaction furnished products in good to excellent yields across various substrates. This environmentally friendly multi-component reaction offers a sustainable method for synthesizing a diverse library of N-substituted isoindolinone derivatives under acidic conditions. The cascade reaction triggers formation of a C-C and two C-N bonds involving carbonyl and carboxyl groups in the presence of nitrile/aniline. Additionally, in the absence of nitrogen source, 3-substituted isobenzofuran-1(3H)-ones were synthesized.