Synthesis of 2-phosphonoheterocycles via base-promoted 5-endo cyclization

[Display omitted] •Fast and easy method to synthesize 2-phosphonodihydrofurans and dihydropyrroles.•Metal-free 5-endo cyclization.•Access to 2-arylated pyrroles. Herein, a synthesis of 2-phosphonodihydrofurans and 2-phosphonodihydropyrroles via 5-endo cyclization of O-and N-propargylated compounds is described. The reaction is promoted by potassium tert-butoxide and allows a fast access to interesting heterocycles which were easily converted into 2-arylated pyrroles under acidic conditions.