A cleft-shaped 2-picolyl-4-amino-1, 8-naphthalimide Tröger’s base (TBNap) was synthesized and employed as a fluorescent ‘turn-on’ chemosensor for the discriminative sensing of volatile halogenated solvents based on an ICT sensing mechanism. TBNap displayed comparatively high fluorescence emission enhancement for chloroform - a potent anesthetic agent and a major constituent of tobacco smoke. The discriminative fluorescence sensing was also seen through visual color changes and was further validated using computational calculations. © 2023 The Author(s). Published by the Royal Society of Chemistry.