Two quinolin-8-ol derivatives, 5-(((1-azido-3-chloropropan-2-yl)oxy)methyl)quinolin-8-ol (ACQ) and 5-(((1,3-diazidopropan-2-yl)oxy)methyl)-quinolin-8-ol (DAQ), were prepared via the O-alkylation of 5-chloromethylquinolin-8-ol salts by azido alcohols under simple and mild conditions with good yields. The structures of ACQ and DAQ were characterized by spectroscopic methods: Fourier transform infrared, elemental analysis, and nuclear magnetic resonance. The ACQ and DAQ were screened as organic inhibitors of carbon steel (CS) corrosion in 1 M HCl using experimental and simulation methods. The experimental findings revealed that ACQ and DAQ greatly improved the corrosion resistance of CS, and DAQ performed better than ACQ. Tafel polarization results showed that quinolin-8-ol derivatives were mixed-type inhibitors with different corrosion rates. The impedance trials data showed that the inhibition performance of ACQ and DAQ reached 93.8% and 96.7% at 10⁻³ M, respectively. The adsorption process of quinolin-8-ol derivatives followed a Langmuir adsorption isotherm and the estimated thermodynamic values suggested physisorption for both ACQ and DAQ. The morphology of the CS surface was analyzed utilizing scanning electron microscopy. The UV–visible spectra showed a strong interaction between ACQ and DAQ with Fe ions between specific atoms. Computational correlations (density functional theory and molecular dynamic simulations) supported the experimental observations.