Organisational chirality

The transfer of chiral information from the nanoscale adsorbed motif to the macroscale organisation of adsorbates leads to another consequence, namely, that switching molecular chirality should also flip the organisational chirality. When enantiopure (5, 5)-TA is adsorbed on Cu(llO), the RAIRS spectra are identical to those of the (R,R) enantiomer, showing that the chemical nature of the adsorbed species is the same for both enantiomers. However, STM and TF.F.D data show that the mirror organisation is now created, yielding a (9 0,-1 2) overlayer (Fig. 5.4). A change in... 

Fig. 17a,b. Snapshots viewed along orthogonal directions showing the molecular organisation within the smectic phase formed hy chiral GB(3.0, 5.0, 1, 2) with c equal to 0.8 at p of 0.30 and T of 0.75 the neighbouring periodic images are also included... 

Metallomesogens have been shown to form helical supramolecular organisations in their mesophases [95]. Chiral oxazoline complexes with various metal ions and six alkyl chains did not show LC behaviour, but when mixed with trinitrofluorenone form achiral smectic A phases [96]. Furthermore, when a branch was included in the structure of the ligands (Fig. 12) the corresponding complexes with copper(II) and palladium(II) form columnar mesophases which have a helical organisation [97]. The presence of the stereogenic centre near the central metal ion in these complexes (Fig. 12) is enough to cause the parallel molecules to stack in a tilted manner with... 

Fig. 12 Chiral metallomesogen based on a chiral oxazoline core and representations of its helical organisation from above (top right) and side-on (bottom right) to the helix axis [97]...

The bitartrate phase is a highly organised structure with a (9 0,1 2) repeat unit cell. Here, we concentrate on this phase to delineate the hierarchies of chiral expression exhibited by this system. 

Barlow S, Raval R (2003) Complex organic molecules at metal surfaces Bonding, organisation and chirality. Surf Sci Rep 50 201... 

Chiral alkoxyallyltin chlorides, prepared in situ with BuSnCB or SnCU as catalyst, add to aldehydes with high degrees of 1,5-, 1,6-, or 1,7-asymmetric induction, which is ascribed to intramolecular interaction between the alkoxyl group and the tin which imposes a highly organised transition state.87... 

A chiral inductor along with the substrate can be trapped in an organised medium. 

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