Collect. Czech. Chem. Commun. 2004, 69, 1195-1230

In,out-Isomerism of Phosphorus Bridgehead Cage Compounds. A Review

Ingmar Bauer* and Wolf D. Habicher*

Institute of Organic Chemistry, Technical University of Dresden, Mommsenstr. 13, 01062 Dresden, Germany


The chemistry and stereochemical peculiarities, especially the phenomenon of in,out-isomerism of bi- and polycyclic compounds with one or more phosphorus bridgehead atoms, are reviewed in the present paper. The appearance of in,out-isomers depends on the ring size of the bi- and polycycles. In general graphic in,out-isomerism becomes only possible in medium sized ring systems and in particular in macrocyclic compounds. However even bicyclic systems containing small rings can be trans-configured if the third chain is long and flexible enough hence giving rise to pseudo-in,out-isomerism. In-phosphorus atoms exhibit a low reactivity in comparison to their out-counterparts. Nevertheless some few examples of reactions at in-positioned phosphorus atoms have been presented. This will potentially open the way to a specific modification of the cavity of such macrobi- and polycyclic compounds. A review with 53 references.

Keywords: Cage compounds; Cryptands; In,out-isomerism; Phosphorus macrocycles; Phosphatranes; Phosphonium salts; Phosphanes; Phosphane oxide; Phosphates.

References: 56 live references.