Ether trimethylene carbonate

A kinetic study of the ring-opening polymerization (ROP) of trimethylene carbonate similarly afforded AG at 383 K of 101.9 kj mol-1, a value which was very close in energy to that found for the production of poly(TMC) from oxetane and C02. Hence, based on these experimental findings, the formation of polycarbonate from the oxetane and C02 coupling reaction was shown to occur via two different or concurrent pathways-that is, the intermediacy of TMC formation, and the subsequent polymerization and/or direct enchainment of oxetane and C02 (Figure 8.16). The presence of small amounts of ether linkages in the copolymer also supported this conclusion. 

A mixture consisting of poly(s-caprolactone-co-trimethylene carbonate) (0.129 mmol), the Step 3 product (1.79 mmol), pyridine (0.62 mmol), and 20.5 ml of CH2CI2 were stirred overnight at ambient temperature. The end-capped polymer was precipitated in diethyl ether and then purified by fractionation using DMF and diethyl ether/methanol, 8 2 the product was isolated in 86% yield. 

While the ROP of five-membered cycUc carbonates is thermodynamically unfavorable and results in a poly(ether carbonate) via decarboxylation of part of the monomer [37], six-, seven- and higher-membered cyclic carbonates and dicarbonates [38-45] were polymerized to obtain polycarbonates without ether sequences. Several 2,2-disubstituted trimethylene carbonate and spirocarbonate monomers were prepared and polymerized in order to tune the polymer properties highly crystalline materials or materials with variable Tg-values were obtained [46-56]. 

Dimethyl carbonate (DMC) is a colorless liquid with a pleasant odor. It is soluble in most organic solvents but insoluble in water. The classical synthesis of DMC is the reaction of methanol with phosgene. Because phosgene is toxic, a non-phosgene-route may be preferred. The new route reacts methanol with urea over a tin catalyst. However, the yield is low. Using electron donor solvents such as trimethylene glycol dimethyl ether and continually distilling off the product increases the yield. ... 

Ethers and ketals in which the Rf chain is separated from the oxygen atom by two or three carbons. In spite of the screen effect due to the di- or trimethylene spacer, fluorine atoms still exert a notable effect. As in the previous case, their synthesis generally requires non conventional methods. 

Oxetane (oxacyclobutane) has been copolymerised successfully with carbon dioxide to give poly(trimethylene ether-carbonate) in the presence of the triethy-laluminium water acetylacetone (2 1 1) catalyst (Table 9.4) [scheme (35)]. The carbon dioxide content in the copolymer produced was ca 20 mol.-%. Attempts to carry out oxetane/carbon dioxide copolymerisation with the diethylzinc water (1 1) catalyst failed to give any copolymer [245],... 

A mixture of 210 g. (1.1 moles) of p-toluenesulfonyl chloride and 189 g. (2.0 moles) of trimethylene chlorohydrin [Org. Syntheses Coll. Vol. 1, 533 (1941)] is stirred and cooled to 8 . To this is added with stirring 320 ml. of 5 A" sodium hydroxide solution at such a rate the temperature of the reaction mixture is held in the range 8-15°. Stirring is continued for 1 hour after the alkali has been added. A second portion of 210 g. (1.1 moles) of p-toluenesulfonyl chloride is added, followed by 320 ml. of 5 N sodium hydroxide solution in the same manner as before. The mixture is stirred for 3 hours longer, and the product is removed by extraction with ether. The ethereal extracts are washed with water and once with 20% sodium hydroxide solution, and then are dried over potassium carbonate. Distillation gives 248-275 g. (50-55%) of y-chloropropyl p-toluenesulfonate boiling at 188-192°/5 mm. 

---