B 1801 (OTTO) Bis-(2-chloro ethyl) ether, 99% Cas 111-44-4 - used as a solvent and soil fumigant. B 1801 (OTTO) Bis-(2-chloro ethyl) ether, 99% Cas 111-44-4 - used in the preparation of macrocyclic polyethers, dibenzo-18-crown-6 polyether and dicyclohexyl-18-crown-6 polyether.