Phosphine (
IUPAC name:
phosphane) is the compound with the
chemical formula PH
3. It is a colorless, flammable, toxic gas. Pure phosphine is odorless, but
technical grade samples have a highly unpleasant odor like
garlic or rotting fish, due to the presence of
substituted phosphine and
diphosphane (P
2H
4). With traces of P
2H
4 present, PH
3 is spontaneously flammable in air, burning with a luminous flame.
Phosphines are also a group of
organophosphorus compounds with the formula R
3P (R = organic derivative). Organophosphines are important in
catalysts where they complex to various metal ions; complexes derived from a
chiral phosphine can catalyze reactions to give
chiral,
enantioenriched products.