Structurally Diverse Polyamides Obtained from Monomers Derived via the Ugi Multicomponent Reaction

Abstract

The combination of the Ugi four-component reaction (Ugi-4CR) with acyclic diene metathesis (ADMET) or thiol-ene polymerization led to the formation of poly-1-(alkylcarbamoyl) carboxamides, a new class of substituted polyamides with amide moieties in the polymer backbone, as well as its side chains. 10-Undecenoic acid, obtained by pyrolysis of ricinoleic acid, the main fatty acid of castor oil, was used as the key renewable building block. The use of different primary amines, as well as isonitriles (isocyanides) for the described Ugi reactions provided monomers with high structural diversity. Furthermore, the possibility of versatile post-modification of functional groups in the side chains of the corresponding polymers should be of considerable interest in materials science. The obtained monomers were polymerized by ADMET, as well as thiol-ene, chemistry and all polymers were fully characterized. Finally, ortho-nitrobenzylamide-containing polyamides obtained by this route were shown to be photoresponsive and exhibited a dramatic change of their properties upon irradiation with light.

Potentially biocompatible polyacrylamides derived by the Ugi four-component reaction

“…Acrylic acid 1 (99%, Aldrich) was freshly distilled before use in Ugi-4CRs. Methyl 4-isocyanobutyrate 4d was synthesized according a procedure mentioned in several publications [40][41][42][43][44][45]. All solvents were used without any kind of purification.…”

“…The Ugi-4CR further provided a strategy for the efficient conjugation of two types of polymers to either a fluorescent molecule, chemical agent or protein [37,38]. With regard to the monomer synthesis, the Ugi-4CR allowed the preparation of polymers with polypeptide-like features [39], a-amide substituted polyamides [40], convertible polyamides [41], and polyurethanes [42].…”

Application of named reactions in polymer synthesis

“…The reaction without catalyst is also an atom-economic and environmentally friendly reaction as only water is expelled as a byproduct and the chemical yields are generally high. Meier's group [91] first studied Ugi-4CR to synthesize highly substituted ,-dienes amide monomers for ADMET polymerization, affording a series of highly diverse substituted polyamides. Like Passerini-3CR, Ugi-4CR can produce polymers via polycondensation or polyaddition processes by using bifunctional components.…”

Monomers and polymers from plant oils via click chemistry reactions

“…Meier and coworkers also reported the successful preparation of medium molar mass polymers containing different functionalities in the main chain from fully renewable dienes based on 10-undecenoic acid using a dithiol as coupling agent. [49][50][51] Thus, an ether-containing diene M37, obtained from 11-bromo-1-undecene and 10-undecenol, an ester-containing diene M38, prepared from methyl 10-undecenoate and 1,3-propanediol, and a diene M39 synthesized via a Ugi four-component reaction, bearing amide groups both in the main as well as side chains, were successfully polymerized SCHEME 2 Chemical structures of thiols used in the transformation of oleochemicals into monomers and polymers.…”