Reduction of [OS~'(P)(O)~](P= porphyrin dianion) with PPh,, ascorbic acid, or N2H,. Hz0 in the presence of ROH and RSH yielded [Oslv (P)(0R),] and [Os'"(P)(SR),], respectively.[OS'~( OEP) B~,](H20EP= octaethylporphyrin) was prepared from [OsV'(OEP)(0) 2] and Br2. The dialkoxyosmium (1V) and dibromoosmium (1V) porphyrin complexes are paramagnetic with measured pew values of 2.27-2.79 pg, which are close to the spin-only values for two ...