Is "BCl"_3 a lewis acid?

1 Answer
Dec 23, 2015

Boron trichloride is a potent Lewis acid,

Explanation:

Boron trichloride is probably the most potent Lewis acid known, and will form adducts with ethers, halides, and amines. While boron trifluoride is also Lewis-acidic, counter-intuitively, the lone pairs on the fluoride, are the right size and shape to donate electron density to the electron deficient boron atom, and the Lewis-acidity of BF_3 is somewhat moderated in comparison.