Tunable hydantoin and base binary organocatalysts in ring-opening polymerizations

Abstract

(Thio)hydantoin (HHyd) and organic superbase binary cocatalyst was illustrated tunable catalytic tool that enabled efficient ring-opening polymerization (ROP) of various cyclic ester monomers. Series of designed HHyds of diversified substitutions...

A Mechanistic Study of the Cu‐catalyzed N‐arylation of Hydantoin with Aryl(TMP)iodonium Salts

“…Energies over the arrows correspond to transition states. Reference for pK a ‐values: N3 [51] and N1 [52] …”

“…Nevertheless, the deprotonation of Hyd is only exergonic when the deprotonated Hyd bonds to Cu yielding intermediates 2 and 9 in Figure 1 Reference for pK a -values: N3 [51] and N1. [52] Scheme 5. Free energies (in kcal/mol) for the N 1 -and N 3 deprotonation of Hyd with 1.…”

Zwitterionic organocatalysis for ring-opening polymerization of cyclic esters

“…12 Enzymatic catalysts certainly possess academic value, although the complexity in their preparation and high costs may limit their practical application. 13,14 Organocatalysts have high catalytic activity and can be operated under mild conditions, such as at room temperature, in conventional solvents, with low catalyst loading, and in short reaction times, [15][16][17][18] due to their combination of efficient catalysis of metal catalysts and green catalysis of enzyme catalysts. Waymouth 19 pioneered the use of DMAP (4-dimethylaminopyridine) in the ring-opening polymerization of lactide in 2001, leading to the preparation of structurally defined polylactic acid and opening up the field of organocatalysis in ring-opening polymerizations.…”

“…Hedrick 29 developed DBUH + and PhCO 2 − ion pairs in 2011, and the effects of hydrogen bond-based activation on monomers and initiators were verified, respectively. Our group 16 used a hydantoin and organic base binary catalyst to efficiently catalyze controlled/living ring-opening polymerization of TMCs in 2020 (Scheme 1, B′).…”