5-Methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one

Chemoenzymatic synthesis of a water-soluble polycarbonate having pendent carboxyl groups on the polymer main chain was achieved by lipase-catalyzed polymerization of 5-methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one (MBC), followed by debenzylation.186 The copolymerization of MBC with TMC using lipase PF catalyst produced the random copolycarbonate.187... 

The lipase-catalyzed polymerization of the disubstituted TMC analog 5-methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one (MBC) was also studied [89]. The bulk polymerization, catalyzed by Pseudomonas fiuorescens lipase for 72 h at 80 °C, gave 97% monomer conversion and product in 97% yield with M = 6100. The benzyl... 

There has been a significant effort to copolymerize TMC with lactones and other carbonate monomers. Matsumura et al. performed copolymerizations of lactide with TMC using porcine pancreatic lipase at 100°C for 168h [113]. They obtained random copolymers with Mw values up to 21000. However, since trimethylene carbonate is known to thermally polymerize at 100 °C (see above), the extent of polymerization that occurs due to activation of monomers at the lipase catalytic triad versus by thermal or other chemical processes is not known [95], Lipase AK-catalyzed copolymerizations of l,3-dioxan-2-one (TMC) with 5-methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one (MBC) were carried out in bulk at 80 °C for 72 h (Scheme 4.27). Although TMC reacted more rapidly than MBC, the product isolated at 72 h appeared to have a random repeat unit distribution [102], Similarly, using Novozym 435 in toluene at 70°C, TMC/PDL copolymerizations were performed and gave random copolymers. 

Al-Azemi, T.F., Harmon, J.P., Bisht, K.S., 2000. Enz3mie-catalyzed ring-opening copolymerization of 5-methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one (MBC) with trimethylene carbonate (TMC) synthesis and characterization. Biomacromolecules 1, 493—500. 

The enzymatic polymerization of 5-methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one produced the corresponding polycarbonate (213). Lipases PF and CA showed high catalytic activity for the polymerization. Debenzylation by catalytic hydrogenation led to the water-soluble polycarbonate with pendent carboxyl group. 

Methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one Medium chain length... 

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