| http://www.w3.org/ns/prov#value | - (a) a phosphonium compound wherein, in the above formula (I), at least one of R1 to R4 is a group represented by the formula (II), R5 to R7 are the same or different, and are a phenyl group, an optionally substituted benzyl group, a naphthylmethyl group, an optionally substituted diphenylmethyl group or an optionally substituted alkyl group, R8 is a hydrogen atom, R9 is a hydrogen atom or a phenyl
|
