| 摘要 |
alpha , beta -Dihaloalkyl isocyanates and a process for the preparation of such compounds by reacting alpha , beta -unsaturated alkyl isocyanates with halogen in the presence of an organic solvent which is inert under the reaction conditions, at from -35 DEG to +90 DEG C. The alpha , beta -dihaloalkyl isocyanates thus obtainable correspond to the formula <IMAGE> I where R1, R2 and R3 are identical or different and each is hydrogen, a saturated aliphatic radical of 1 to 10 carbon atoms, a cycloaliphatic radical of 3 to 12 carbon atoms, an araliphatic radical of 7 to 11 carbon atoms or an aromatic radical of 6 to 10 carbon atoms, or R1 and R2 together with the carbon atom on which they are present as substituents are cycloalkyl of 3 to 7 ring members, and X is halogen. The compounds are valuable intermediates for the preparation of dyes, surface-coating intermediates, crop protection agents and drugs. |
