About 15 years ago, a major new class of polymer, the dendrimers, began to be synthesized. Dendrimers are part of a larger class of polymer, hyperbranched polymers, which have also become more actively studied. Industry is very interested in dendritic and hyperbranched polymers because of their highly branched molecular structures, leading to their applications, for example, as viscosity controllers, highly reactive intermediates and release agents for chemicals (drugs, flavors, dyes, etc.). The need to name such polymers systematically is widely recognized. However, if even oligomeric dendrimers are named using organic chemistry nomenclature, very long names result which obscure the chemical constitution and the Commission for Nomenclature in Organic Chemistry (CNOC) has aborted its attempt to define their nomenclature. It is recognized that an approach using the concepts of structure-based macromolecular nomenclature has much more chance of success.
A start in naming dendrimers has already been made in the literature by Newkome et al (J. Polym. Sci. 1993, 31, 641; https://doi.org/10.1002/pola.1993.080310307). Unlike that nomenclature, the nomenclature of both dendrimers and hyperbranched polymers according to the project is based on principles of structure-based nomenclature of regular single-strand organic polymers, but embraces also dendrimers and hyperbranched polymers of more general, less regular structures. In addition, an integral part of the work will also be the development of the basic terminology, enabling different types of branching, or molecular architecture to be described precisely. Even that does not exist at present. The project has undergone a thorough feasibility study, the results of which have been discussed by the Commission.
March 2011 update – Major progress has been made since the project was launched. Basic terms pertinent to dendritic and hyperbranched oligomers and polymers have been defined. The main principles of a new method of naming them, based on the concept of constitutional repeating unit and providing for core and end units were elaborated. The method will now be tuned to meet requirements and checked on the basis of numerous examples from the literature; if necessary, the rules will be modified and additional rules added. In addition to defining a structure-based nomenclature, an attempt will also be made to design a source-based nomenclature. The task group plans to have a final version at the Puerto Rico meeting.
January 2017 update – The provisional recommendations titled “Nomenclature and Terminology for Dendrimers with Regular Dendrons and for Hyperbranched Polymers” is available for public review till 31 May 2017.
March 2019 update – IUPAC Recommendations published: Fradet, A., Chen, J., Hellwich, K., et al. (2019). Nomenclature and terminology for dendrimers with regular dendrons and for hyperbranched polymers (IUPAC Recommendations 2017). Pure and Applied Chemistry, 91(3), pp. 523-561; https://doi.org/10.1515/pac-2016-1217
Last update 11 March 2019