Synthetically induced 1->4-C branching motif - An access towards dense urethane connecting dendritic scaffolds and application in nuclear track detection

Abstract

A series of dumbbell-shaped urethane connecting polyoleifinic dendrimers, are synthesized from commercial AB sub(2) monomer through the concept of post-generative synthetic induction of novel 1->4-C branching motif in divergent and convergent growth methodology using carbamoyl chloride reactivity. A synthetic protocol is conducted through the iterative process of O-carbamoyl-allylation of hydroxyls followed by Upjohn dihydroxylation of the allylic double bonds, leading to protection/deprotection free divergent pathway. In parallel, convergent growth route gains dendrimers in relatively good yields. Also, the process of O-carbonyloxy-allylation of [G-1] polyol affords urethane-carbonate framework providing access to 1->2-C branching further. Incorporation of current branching motif results in dendritic scaffold with dense periphery at lower generations itself. Free radical cast polymerization of [G-0.5] dendrimer with allyl diglycol carbonate (ADC) produces thermoset polymer films, showing good sensitivity and ability to permanently record nuclear tracks.