Oxetane

From Wikipedia, the free encyclopedia

Paclitaxel. Oxetane ring visible at right.
Paclitaxel. Oxetane ring visible at right.

Oxetane refers both to the parent compound (C3H6O) and to the class of heterocyclic compounds having a four-membered ring with three carbon atoms and one oxygen atom.

Paclitaxel (Taxol®) is an example of a natural product containing an oxetane ring.

[edit] dioxetanes

The dioxetanes are organic compounds responsible for many instances of bioluminescence. In the 1960s biochemists came to the conclusion that these compounds had a fleeting existence in fireflies, glow-worms and other luminescent creatures. The instability of these four-membered cyclic peroxides meant that the hypothesis could not be proved. Then in 1968 the first example of a stable dioxetane was made during the course of other research at the University of Alberta in Edmonton. This first example was 3,3,4-trimethyl-1,2-dioxetane prepared as a yellow solution in benzene. When heated to 333K it decomposed smoothly rather than explosively as many peroxides do. Moreover is decomposed to propanone and ethanal with the emission of pale blue light.[1]

The second example of a dioxetane was made shortly after. It was the symmetrical compound 3,3,4,4-1,2-dioxetane. This could be obtained as pale yellow crystals that sublimed even when kept in the refrigerator. Benzene solutions of this compound also decomposed smoothly with the emission of blue light. By adding compounds that normally fluoresce in UV light the colour of the emitted light could be altered. Because theoretical scientists seek to understand the mechanism of light emission this second example rapidly became the most studied symmetrical compound ever.[2] .The luminescent bangles and necklaces worn at outdoor evening events make use of a dioxetane derivative called dioxetanedione that decomposes to carbon dioxide. Other dioxetanes are used in clinical analysis where the ability to detect very faint light emission allows chemists to detect very low concentrations of body fluid constituents. [3]

[edit] References

  1. ^ Luminescence in the thermal decomposition of 3,3,4-trimethyl-1,2-dioxetane,Canadian Journal of Chemistry Volume 47, p 709 (1969) by K.R.Kopecky and C. Mumford
  2. ^ Preparation and Thermolysis of some 1,2-dioxetanes, Canadian Jouranl of Chemistry Volume 53, pa 1103 (1975)by K.R. Kopecy et al.
  3. ^ US Patent No. 5,330,900 to Tropix Inc.