What is the function of ZnCl2 (anhydrous) in Lucas test for distinction between 1∘,2∘ and 3∘ alcohols.
Lucas Reagent is (ZnCl2 + HCl)(ZnCl2 + HCl) Because of ZnZn has vacant d orbitals, ZnCl2ZnCl2 is a Lewis acid. The oxygen in - OH - OH forms a coordination connection with Zinc, or compounds with it. Oxygen takes on a positive charge, whereas ZnZn takes on a negative charge. So, because oxygen now has a positive charge, a poor leaving group - OH - OHhas been transformed into a good leaving group (increased electronegativity).
