Preparation of 3-formyl-5,6-dihydro-2H-pyran

摘要

3-Formyl-5,6-dihydro-2H-pyran is prepared by conversion of acrolein in the presence of water, acids and halohydrocarbons of 1 to 6 carbon atoms and 1 to 6 halogen atoms as solvents at from 60 DEG to 150 DEG C. The 3-formyl-5,6-dihydro-2H-pyran obtained by the novel process is a valuable starting material for the preparation of dyes and crop protection agents.