A compound represented by the following general formula (I):
[wherein R
1
represents hydrogen atom, or an alkyl group, R
2
represents a hydroxyalkyl group, or a triarylmethyloxyalkyl group, or R
1
and R
2
combine together to represent —C(R
3
)(R
4
)— (R
3
and R
4
represent hydrogen atom, an alkyl group, or hydroxyl group, or R
3
and R
4
may combine together to represent oxo group), or —C(R
5
)(R
6
)—O—C(R
7
)(R
8
)— (R
5
to R
8
represent hydrogen atom, an alkyl group, or hydroxyl group, or R
5
and R
6
may combine together to represent oxo group, and R
7
and R
8
may combine together to represent oxo group); Ar
1
to Ar
4
independently represent an aryl group (the aryl group may have 1 to 5 of the same or different substituents), *1 to *4 indicate asymmetric carbons, and configurations are cis between *1 and *2, cis between *3 and *4, and trans between *2 and *3]. An optically active phosphine ligand which can be easily synthesized and gives a transition metal complex showing superior asymmetric catalyst activity is provided.