Платина(IV) оксид

Химические свойства

Platinum dioxide, also known as Adams catalyst, is a dark brown powder, a hydrated form of platinum (IV) oxide (PtO2), produced by heating chloroplatinic acid (H2PtCl6) with sodium nitrate (NaNO3). Platinum nitrate is produced, and this decomposes to Platinum (IV) oxide with evolution of NO2 and oxygen. It is used in hydrogenations of alkenes to alkanes, nitro compounds to aminos, and ketones to alcohols. The actual catalyst is not the oxide but finely divided platinum black, which forms during the hydrogenation reaction.

Использование

As catalyst in hydrogenations. The actual catalyst is platinum black which is formed in situ by reduction of the PtO2 by the hydrogen used for the hydrogenation. Especially useful for reduction at room tempereture and hydrogen pressures up to 4 atmospheres. Suitable for the reduction of double and triple bonds, aromatic nuclei, carbonyl groups, nitro groups, and nitriles.

прикладной

Platinum (IV) Oxide commonly referred to as Adam’s Catalyst is used frequently in organic synthesis reactions, mainly catalytic hydrogenation. The compound itself shows no cytotoxicity in cells of the pulmonary origin when compared to its PtCl4 counterpart. It has also been used as a catalyst in amperometric biosensors that are based on oxidase enzymes.

Методы производства

PtO2 is obtained by reduction in chloroplatinic acid with formaldehyde or by fusing chloroplatinic acid with sodium nitrate.

Общее описание

Platinum(IV) oxide has been used for the reduction of citernyl bromide to form (S)-3,7-dimethyloctylbromide. Prepared by Adams′ nitrate fusion method.