Platinum
Pure platinum is a lustrous, ductile, and malleable, silver-white metal. Platinum is more ductile than gold, silver or copper, thus being the most ductile of pure metals, but it is less malleable than gold. The metal has excellent resistance to corrosion, is stable at high temperatures and has stable electrical properties. Platinum does oxidize, forming PtO, at 500 °C; this oxide can be easily removed thermally. It reacts vigorously with fluorine at to form platinum tetrafluoride. It is also attacked by chlorine, bromine, iodine, and sulfur. Platinum is insoluble in hydrochloric and nitric acid, but dissolves in hot "aqua regia" (A mixture of nitric and hydrochloric acids), to form chloroplatinic acid, HPtCl.
Sharpless epoxidation
Although it is the least reactive metal catalyst for epoxidations, vanadium is highly selective for alkenes with allylic alcohols. Early work done by Sharpless shows its preference for reacting with alkenes with allylic alcohols over more substituted electron dense alkenes. In this case, Vanadium showed reverse regioselectivity from both m-CPBA and the more reactive molybdenum species. Although vanadium is generally less reactive than other metal complexes, in the presence of allylic alcohols, the rate of the reaction is accelerated beyond that of molybdenum, the most reactive metal for epoxidations.