PURPOSE: To provide the subject new compound manifesting both highly excellent reactivity and reaction characteristics as a ligand, giving high branch/linear form ratio, and capable of producing an intermediate for medicines by hydroformylation using the same.

CONSTITUTION: The objective compound having bicyclo[2,2,1]heptane skeleton of the formula (R1-R4 are each l-8C alkyl, 6-18C aryl or 7-18C aralkyl, R1 and R2 and/or R3 and R4 are each alkyl, aryl or aralkyl which may also be linked to each other via a bond except for P atom), e.g. endo, endo-2,5- bis[(diphenylphosphinyl)oxy]bicyclo