LiCl is soluble in organic solvents while the chlorides of other alkali metals are not explain.

Explanation

As we move down a grou, the cationic radius increases, which decreases the polarising power of the cation, which ultimately decreases the polarising power of the cation, which ultimately decreases the covalent character of the compound. Since LiCl is the most covalent compound among all the alkali metal chlorides, it is soluble in organic (non-polar) solvents while the rest are not.