Intermolecular chiral

Within this historical setting, the actual birth of stereochemistry can be dated to independent publications by J. H. van t Hoff and J. A. Le Bel within a few months of each other in 1874. Both scientists suggested a three-dimensional orientation of atoms based on two central assumptions. They assumed that the four bonds attached to a carbon atom were oriented tetrahedrally and that there was a correlation between the spatial arrangement of the four bonds and the properties of molecules, van t Hoff and Le Bell proposed that the tetrahedral model for carbon was the cause of molecular dissymmetry and optical rotation. By arguing that optical activity in a substance was an indication of molecular chirality, they laid the foundation for the study of intramolecular and intermolecular chirality. 

Work by Irie et al. on the control of intermolecular chiral l,l -binapthyl fluorescence quenching by chiral amines [66] and the use of 1,1 -binaphthyl in the recognition of chiral amines by Cram [67] were the inspiration behind the design of 26 (R or S). Chiral recognition of saccharides by 26 (R or S)... 

In modem terminology, the core of Marckwald s definition is the conversion of an achiral substance into a chiral, nonracemic one by the action of a chiral reagent. By this criterion, the chiron approach falls outside the realm of asymmetric synthesis. Marckwald s point of reference of course, was biochemical processes, so it follows that modern enzymatic processes [30-32] are included by this definition. Marckwald also asserted that the nature of the reaction was irrelevant, so a self-immolative reaction or sequence such as an intermolecular chirality transfer in a Meerwein-Pondorf-Verley reaction would also be included ... 

With a four-level concept of chirality, the question of how chirality can be transferred from one level to an adjacent level is of fundamental interest. In particular, the mapping of the chirality of a molecule (second level) onto the liquid crystal phase (third level) or vice versa—the intermolecular chirality transfer—will be discussed within the scope of this chapter. But what does chirality transfer really mean The questions of how much chirality a molecule possesses or how much chirality can be transferred to an adjacent level are not allowed in the sense of transport of an amount of chirality from one level to another. Chirality is an information which can be transferred from one level to the other without being lost in the level from which it is originated. There are two possible statements [10] ... 

Intermolecular chiral recognition using the quinine carbamate compounds as analytes was also investigated. The results from 2D NMR studies including 1H 15 N heteronuclear single quantum coherence (HSQC) show that these CILs (25 and 26) exhibit inframolecular as well as intermolecular enantiomeric recognition (Fig. 19). 

Hopkins TA, Metcalf DH, Richardson FS. Intermolecular Chiral Recognition Processes Probed by Chiroptical Luminescence. Chirality 2008 20 511-523. 

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