What is gem-dihalide? Give one example and explain its preparation.

1.	What is gem-dihalide? Give one example and explain its preparation.
Answer» Solution :(i) If two halogen atoms are attached to one carbon atom of alkyl HALIDE . It is named as gemdialide e.g. , `CH_(3) - CH Cl_2` (ethylidene dichloride ) (II) Preparation of `CH_(3) - CHCl_(2)` `underset("Acetaldehyde") (CH_(3) CHO) + PCl_(5) to CH_(2) = underset(Cl) underset(\|)(C)HCl + POCl_(3)`

Discussion