Abstract Corrections to the first-order semiclassical description of the electromagnetic breakup of 8B in heavy-ion collisions are studied. Second- and third-order corrections to the Coulomb dissociation of light projectiles in heavy-ion collisions are calculated in an approximation for small adiabaticity parameters. Quantum mechanical diffraction effects are investigated in a simple approximation obtained from Glauber theory. The methods are applied to the 8B breakup at projectile energies of 46.5 and 250 A·MeV. Implications on the extraction of the astrophysical S-factor of the inverse 7Be(p,γ) 8B reaction, which is relevant to the solar neutrino problem, are discussed.