title: Tailored functionalization of polyphenol-based molecular platforms.
abstract: General and efficient methods for selective modification of macrocyclic oligomers are rare, mostly because restricting a reaction to a defined number of identical functional groups is difficult to achieve. This work describes a unique, general, and rational methodology for the iteroselective functionalization of polyphenolic platforms by N-tert-butylaminocarbonyl (Bac) groups. The methodology consists of reacting the oligomeric platform with t-BuNCO and an inorganic base in an apolar solvent. This very simple one-step procedure has been applied to various calix[4, 5, 6, and 8]arenes, and in all cases, calixarenes with a single leftover phenolic moiety were isolated in high yields (>90%). Interestingly, this so-called "all-but-one" methodology gives a straightforward access to calixarenes displaying inherent chirality. It is also shown that the Bac group can be used as a protective group. Thus, the all-but-one methodology has been used for the efficient monofunctionalization of a key precursor platform, illustrating its huge potential for the tailored synthesis of sophisticated macrocyclic oligomers.
authors: Laboratoire de Chimie Organique, Université Libre de Bruxelles (ULB) , Avenue F.D. Roosevelt 50, CP160/06, B-1050 Brussels, Belgium.
authors: Roy
authors: R
authors: Lavendomme
authors: Axel
authors: A
authors: Leroy
authors: Michel
authors: M
authors: Luhmer
authors: Ivan
authors: I
authors: Jabin