Social isomerism

Scheme 10.10 (a) social isomerism in capsule (10.54)2, (b) isomeric constellations in (10.54)2. If the capsule holds a mixture of two chloroform and one C1CH(CH3)2 guest then two different isomeric arrangements are possible in which the C1CH(CH3)2 is in the middle or at one end (reproduced with permission from Reference 46). 

A novel type of stereoisomerism within the cavity of a cahx[4]arene-based caging ligand 290 as a resnlt of different orientations of solvent gnests (social isomerism) has been reported for the first time by D.N. Reinhoudt and coworkers... 

Reinhoudt s social isomerism (see Sect. 3.1.1) is described in [92] to appear in the cage complexes of 429 in the case of co-encapsulation by Scheme 3.93 of the solvent guests with para-substituted toluene derivatives. In the case of... 

One of the subtlest cases of social isomerism was encountered with the isotopic substitution of one of the ends of an encapsulated molecule. Equilibrium isotope effects are somewhat of a rarity in molecular recognition but are not insignificant [29, 30]. Deuterium substitution of C-H bonds in molecules tends to make behave as... 

Mixtures of pheromones can often be complex and demanding to separate, particularly when isomers of molecules are present. This is particularly acute in the study of social insect cuticular hydrocarbons and which are often complex mixtures of 50 or more different hydrocarbons of increasing chain length (Figure 8). For these mixtures the separation of isomeric hydrocarbons such as 9-, 11-, and 13-methyl-heptacosane is not possible, which has a consequent impact on peak integrations and statistical correlation of these data with colony function. 

An intriguing class of hydrogen-bonded self-assembled molecular capsule is that of the Rebek dimeric capsules based on deep cavitands prepared from resorcin[4] arene derivatives [3,12,22], The importance of this class of dimeric capsules arises from their elongated shape which resulted in anisotropic imsymmetrical cavities which gave birth to several phenomena such as social and constellational isomerism, [23a-b] which could not be observed in the bulk or in other capsules... 

Fig. 32.8 (a) Social isomers (A and B) generated from the self-assembly of dimeric capsule 12 12 in CHCI3 (blue) in the presence of p-ethyltoluene. Both extremes of p-ethyltoluene (ethyl and methyl groups) are highlighted in different colors (pink and green, respectively), (b) Possible arrangements for co-encapsulated CHCI3 (blue) and isopropyl chloride 18 (pink) within capsule 12 12. Complexes II and III (and IV and V) are isomeric constellations... 

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