Sequential Triple Click Approach toward Polyhedral Oligomeric Silsesquioxane-Based Multiheaded and Multitailed Giant Surfactants

This letter reports a sequential triple click chemistry method for the precise synthesis of functional polyhedral oligomeric silsesquioxane (POSS)-based multiheaded and multitailed giant surfactants. A vinyl POSS-based heterobifunctional building block possessing two alkyne groups of distinct reactivity was used as a robust and powerful dicicable precursor for ready access to a variety of POSS-based shape amphiphiles with complex architectures. The synthetic approach involves sequentially performed strain-promoted azide-alkyne cycloaddition (SPAAC), copper-catalyzed azide-alkyne cycloaddition (CuAAC), and thiol-ene click coupling (TECC). Specifically, the first SPAAC reaction was found to be highly selective with no complications from the vinyl groups and terminal alkynes in the precursor. The method expands the toolbox of sequential click approaches and broadens the scope of synthetically available giant surfactants for further study on structure-property relationships.