One-Step Construction of 2‑Methylquinazolin-4(3<i>H</i>)‑ones Using Solid Calcium Carbide as an Alternative\nto Gaseous\nAcetylene

2-Methylquinazolin-4(3<i>H</i>)-ones were efficiently\nconstructed using solid calcium carbide as an alkyne source, 2-aminobenzamides\nor 2-aminobenzohydrazides as substrates, and <i>p</i>-tolylsulfonyl\nazide as a mediator through simultaneous formation of two C–N\nbonds in one step. The salient features of this protocol are the use\nof an inexpensive, abundant and easy-to-use alkyne source as a substitute\nfor flammable and explosive gaseous acetylene, low-cost catalyst,\nwide substrate scope, satisfactory yield, and simple manipulation.\nThis method can also be extended to gram scale.