periodinanes

Periodinanes are a class of hypervalent iodine compounds in which iodine exists in the +5 oxidation state and functions as mild, selective oxidants in organic synthesis. The best-known periodinanes are derived from o-iodobenzoic acid and related aryl carboxylates, and typically feature a cyclic, hypervalent iodine(V) center. Notable examples include 2-iodoxybenzoic acid (IBX) and Dess–Martin periodinane (DMP). These reagents are prepared by oxidation of iodobenzoic acid derivatives to the iodine(V) periodinane form and are often used in solution or as solids after purification.

In use, periodinanes oxidize alcohols to carbonyl compounds under mild conditions with good chemoselectivity and tolerance of sensitive functional groups. Primary alcohols are generally oxidized to aldehydes, while secondary alcohols become ketones. They are considered milder alternatives to chromium-based or Swern-type oxidations and are valued for operational simplicity, though stoichiometric waste and cost can be concerns.

Limitations and properties: Periodinanes are strong oxidants and must be handled under appropriate safety precautions; many derivatives are moisture sensitive and can be unstable if not stored properly. IBX is often used as a solid with limited solubility, while DMP offers higher reactivity and better solubility in some solvents but can be more expensive. Scale-up can be challenging due to cost and potential hazards, and the byproducts are typically iodoarene fragments that may require disposal.

See also: hypervalent iodine, IBX, Dess–Martin periodinane, PIFA, PIDA.