Anchors, complex, templates with

Najera and coworkers introduced a new class of cyclic alanine templates (227, equation 59), the structure of which was anchored on Schollkopf s bislactim ether . Palladium-catalyzed allylations of the chiral pyrazinone derivative 227 with allylic carbonates (228) as substrates led to the formation of y,i5-unsaturated amino acids (229a-c) under very mild and neutral reaction conditions, whereas the required base for enolate preparation has been generated in situ from the allylic carbonate during jr-allyl complex formation. With this protocol in hand, the alkylated pyrazinones 229 were obtained with excellent regio- and diastereoselectivities (>98% ds). Finally, hydrolysis with 6 N aqueous HCl under relatively drastic conditions (150 °C) led to the free amino acids. 

However, the formation of mesophases inside the two-dimensional confinement of nanopores can be complex. For example, a model compound based on the triphenylene motif was melt-infiltrated into AAO hard templates. It was found that homeotropically anchored columns whose growth starts from the pore walls compete with planar columns in the center of the pores that proceed along the pore axes, i.e., along the direction that is free... 

However, Tourillon et al. were able to create Co and Fe nanotubes (30 nm diameter and 6 pm long) without the use of a molecular anchor by utilizing a track-etched polycarbonate template. They hypothesized that the metal cations in the solution complexed with the groups... 

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