SYNTHESES OF POLYAMINE- AND POLYNITRILE DENDRIMERS FROM A NONA-ARM CORE UPTO 144-NITRILE USING VOGTLE'S ITERATION

The Michael reaction of acrylonitrile applied to a nonol core 3 yielded a nona-nitrile 4 which was used as the starting point for an iterative divergent synthesis of polynitrile and polyamine dendrimers using the seminal Vogtle strategy. The nona-nitrile 4 was reduced to the nona-amine 5 using BH3 . THF in refluxing THF or BH3 . Me2S in THF at 20 degrees C followed by methanolysis of the borane adduct. The second iterative step was unchanged and consisted in the Michael reaction of the nona-amine 5 with acrylonitrile to give the octadeca-nitrile 7. This iterative sequence was applied up to the 144-CN dendrimer.