Informational Polymers with Precise Carbamate Sequences

Abstract

Sequence-defined oligocarbamates were synthesized by orthogonal iterative chemistry on a modified Wang solid support. In this approach, amino alcohol building blocks, containing either primary or secondary amines, were used in order to obtain on-demand either a classical urethane motif −NH–CO–O– or a N-substituted urethane linkage −NR–CO–O–. Hence, aperiodic carbamate sequences could be easily prepared in this work. Polymers with different monomer sequences and chain-length were synthesized. Characterization by NMR, SEC and ESI-MS indicated formation of near-monodisperse polymers. Furthermore, these informational oligocarbamates were sequenced by MS/MS. Very interestingly, it was found that a fully orthogonal fragmentation of −NH–CO–O– urethane motifs occurs in these macromolecules.