Triptycenes, review

Other structural concepts evolved, one of them being triptycenes (55). Here, additional wings are introduced into the molecules by Diels-Alder type reactions. The glass-forming properties are improved by the propeller-like rigid structure [89]. We end our overview of the different classes of molecular glasses with these materials and note that the number of published structures is growing every year. More details on the different materials can be found in one of the recent chemical reviews [102-104]. 

Jones Mangold Plieninger Tetrahedron 1962,18, 267 Plieninger Wild Westphal Tetrahedron 1969, 25, 5561. " Wittig Niethammer Chem. Ber. 1960, 93, 944 Wittig Harle Knauss Niethammer Chem. Ber. 1960, 93, 951. For a review of triptycene, see Skvarchenko Shalaev Klabunovskii Russ. Chem. Rev. 1974, 43, 951-966. 

As is obvious from this review the subject of 1,6-disubstituted triptycenes is very much in its infancy, but it is hoped that new workers will be attracted to the field, bringing with them fresh ideas and expertise spawned in other areas of research. 

Reviews of general interest this year have concerned force-field calculations (by Altona), Bredt s rule, adamantane rearrangements," triptycene chemistry, the relation between mass-spectral behaviour and thermolytic and photolytic reactivity, the removal of orbital symmetry restrictions to organic reactions, catalysis by transition metals of symmetry-disallowed reactions, and [2,2]paracyclophanes, many of whose reactions lead to bridged or cage molecules. 

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