Discrete organic nanotubes based on a combination of covalent and non-covalent approaches

Tubular organic nanostructures offering precise control over inner and outer surface functionality represent attractive building blocks for the bottom-up approach in nanotechnology, as well as for the development of future materials and biological applications. In this review, the current state of the art in creating organic nanotubes is summarized, focusing on the chemistry behind tubular structure formation. The discussion of general design principles, which are altogether inspired by Nature and combine covalent and noncovalent synthesis, is followed by detailed treatments of the individual approaches including helices and their assemblies, stacked rings and rosettes, as well as cylindrical micelles and rolled sheets. The authors provide a critical evaluation of past accomplishments, promising current developments, and future challenges in this fascinating and highly interdisciplinary research topic.