Carbosilane dendrimeric carbodiimides: site isolation as a lactamization tool

Area of Science:

• Organic Chemistry
• Dendrimer Chemistry
• Supramolecular Chemistry

Background:

• Carbodiimides are versatile functional groups with applications in synthesis.
• Dendrimers offer unique properties due to their branched architecture.
• Site isolation is crucial for controlling reactivity in dendritic structures.

Purpose of the Study:

• To synthesize carbosilane dendrimers with carbodiimide cores.
• To investigate the site isolation effect in different generations of these dendrimers.
• To explore the utility of these dendrimers in mediating organic reactions.

Main Methods:

• Convergent and divergent synthesis strategies were employed.
• Hydrosilylation and Grignard reactions were used for building block synthesis.
• Fourier-transform infrared (FT-IR) spectroscopy monitored dilution experiments to assess self-aggregation.

Main Results:

• Three generations of carbosilane dendrimeric carbodiimides were successfully synthesized.
• Site isolation was confirmed for second and third-generation dendrimers, with only the first generation showing self-aggregation.
• The dendrimeric carbodiimides effectively mediated lactamization reactions to yield homodiketopiperazines.

Conclusions:

• The synthesized carbosilane dendrimeric carbodiimides exhibit tunable site isolation properties.
• These dendrimers serve as effective catalysts or mediators for specific organic transformations.
• The study highlights the potential of dendritic architectures in controlling molecular interactions and reactivity.