First Example of Anionic Polymerization with Azo-Containing Radical Initiators:  Anionic Ring-Opening Polymerization of Cyclic Carbonate Initiated by Azobis(isobutyronitrile) and Related Azo Initiators

Anionic ring‐opening polymerization of a five‐membered cyclic carbonate having a glucopyranoside structure

“…In recent years, ring‐opening polymerizations of cyclic carbonates have been widely studied by many researchers to synthesize polycarbonates. Particularly, ring‐opening polymerizations of cyclic carbonates with organometals, metal alkoxides, or organobases have become one of the most promising methods to obtain well‐defined polycarbonates 6–16. It is well known that anionic ring‐opening polymerizations of six‐ and seven‐membered cyclic carbonates such as cyclotrimethylene carbonates and cyclotetramethylene carbonates easily proceed under mild conditions.…”

The anionic ring-opening polymerization of five-membered cyclic carbonates fused to the cyclohexane ring

“…[1][2][3] For their synthesis, various procedures have been used, that is, (i) the polycondensation between the carbonate derivatives and diols, 4 (ii) the ring-opening polymerization of cyclic carbonates, [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] and (iii) the alternating polymerization of epoxides with carbon dioxide. Among these procedures, the ring-opening polymerizations of cyclic carbonates have the potential to control the molecular weight and to induce copolymerization with other cyclic monomers.…”

“…Six-membered cycles (or larger) using anionic initiators tend to polymerize smoothly, yielding the corresponding polycarbonate at a lower temperature (o100 1C). [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] In contrast, the anionic ring-opening polymerization of the fivemembered ring is thermodynamically unfavorable and proceeds at a higher temperature (4150 1C), causing the elimination of carbon dioxide to produce a copolymer that consists of both carbonate and ether linkages. [20][21][22][23][24][25] However, we reported that the anionic ringopening polymerization of a five-membered cyclic carbonate (MBCG) (Figure 1) possessing the a,D-glucopyranoside structure proceeded even at 0 1C to produce an aliphatic polycarbonate without the elimination of carbon dioxide.…”

Anionic Ring-Opening Polymerization of Methyl 4,6-O-Benzylidene-2,3-O- carbonyl-α-d-glucopyranoside: A First Example of Anionic Ring-Opening Polymerization of Five-Membered Cyclic Carbonate without Elimination of CO2

“…Aliphatic polycarbonates are very attractive materials because of their biocompatibility and biodegradability. − For their synthesis, two procedures have been used, i.e., (a) a polycondensation between activated carbonate derivatives and diols and (b) a ring-opening polymerization of cyclic carbonates. − The latter should proceed by a chain polymerization and have potential to control molecular weight of the resulting polymer.…”

“…The anionic ring-opening behavior of the cyclic carbonates depends on their ring size. Six- or larger-membered cycles tend to polymerize smoothly to yield the corresponding polycarbonate at lower temperature (<100 °C) by anionic initiators. − In contrast, the anionic ring-opening polymerization of the five-membered ring is thermodynamically unfavorable and proceeds at higher temperature (>150 °C), causing elimination of carbon dioxide to give a copolymer consisting of both carbonate and ether linkages. − …”