ACTIVE‐BAPO – A Versatile Transfer Agent for Photoactive Bis(acyl)phosphane Oxide Units

• Published in: Chemistry : a European journal Vol. 29; no. 26; pp. e202203842 - n/a
• Main Authors: Widera, Anna, Conti, Riccardo, Cosola, Andrea, Fäh, Ashling, Thöny, Debora, Sangermano, Marco, Levalois‐Grützmacher, Joëlle, Grützmacher, Hansjörg
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 08-05-2023; Wiley-VCH Verlag
• Subjects: Additives; Amino acids; Amino groups; bis(acyl)phosphane oxide; Chemical Sciences; Chemistry; Crosslinking; Dendrimers; Free radical polymerization; Free radicals; ligation; Monomers; multiple photoinitiators; Photoinitiators; polymerization; Rheological properties; Rheology; Substrates; Succinimide; multiple photoinitiators; polymerization; bis(acyl)phosphane oxide; dendrimers; ligation
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202203842

A N‐hydroxy succinimide (NHS) ester substituted bis(acyl)phosphane oxide (ACTIVE‐BAPO) was prepared by phospha‐Michael addition and used for an easy one‐step BAPO ligation with substrates containing primary amino groups, such as amino acids, proteins, and poly(amidoamine) (PAMAM) dendrimers. Thereby, a range of new molecular and polymeric photoinitators was obtained. Real‐time photo‐rheology experiments demonstrated the outstanding efficiency of the PAMAM BAPOs as photoinitiators for free radical polymerization. Remarkably, it is found that PAMAM BAPOs also act as crosslinking agents to convert monofunctional methacrylate monomers into thermosetting networks without any further additives. Depending on the number of the attached BAPOs, thermosets with a different degree of crosslinking and swelling capability in water were obtained.
Active BAPO ‐ An NHS ester substituted bis(acyl)phosphane oxide (BAPO) is synthesized by phospha‐Michael addition and used as the first versatile transfer agent for the grafting of photoactive BAPO units. Amino acids, porcine skin, and poly(amido)amine (PAMAM) dendrimers were functionalized with the photoactive units and used for the synthesis of thermosets with a different degree of crosslinking.