Polymerization of 3,3,3‐trifluoro‐1,2‐epoxypropane with organozinc compounds and alkali metal alkoxides

Abstract

Experimental partAll experiments related to the polymerization reaction were carried out under nitrogen atmosphere to exclude oxygen and moisture.Reagents: (S)-3,3,3-Trifluoro-l,2-epoxypropane (TFEP; enantiomeric excess (e. e.) = 75) was prepared from 3,3,3-trifluoropropene by fermentation with Nocardia corallina by Nippon Mining Co. Ltd., and purified by distillation after refluxing over calcium dihydride. Commercial benzene, methanol and diethylzinc were purified by the usual methods '). 1,2-Dimethoxyethane, 1 -methoxy-2-propanol and 2-methyl-2-propanol were purified by distillation after refluxing over calcium dihydride. [C2H5ZnMP12[ZnMP212 (5)13) (MP: CH30CH2CH(CH3)O-) were prepared by the methods as previously reported. Alkali metal tert-Makromol. Chem., Rapid Commun.

Polymerization of Ethylene Oxide, Propylene Oxide, and Other Alkylene Oxides: Synthesis, Novel Polymer Architectures, and Bioconjugation

“…These materials offer potential for application as solid polymer electrolytes and showed promising Li-ion conductivity. In the early 1990s, Japanese scientists investigated the properties of fluorinated polyethers. , The authors found that high molecular weights and yields could be easily achieved when employing organozinc compounds as catalysts for (anionic) coordination polymerization. Nozaki et al recently revisited the polymerization behavior of fluorinated epoxide monomers and studied regioregularity and tacticity in case of enantiopure epoxides. , …”

Regio-controlled ring-opening polymerization of perfluoroalkyl-substituted epoxides

“…Only one report has appeared on regioregular polyether formation from 3,3,3-trifluoropropylene oxide. 11,12 Generally, standard synthetic strategies for non-fluorinated compounds cannot be directly applied to the reaction of organofluorine compounds because of their unusual properties. For example, highly fluorine-substituted molecules or fragments display a low affinity with general organic or aqueous solvents.…”

“…Generally regioregular ring-opening polymerization of propylene oxide proceeds through successive nucleophilic attacks on the less hindered methylene carbon rather than the methine carbon. 11,24 Accordingly, it is reasonable to assume that the methine carbon retains its configuration and that isotactic polyethers are obtained by using enantiopure epoxide. As a result, the methylene peak at the lowest field of the four should be regarded as an mm-triad.…”

“…In contrast to the polymers from 1 and 3, the polymer obtained from 4 had a regioirregular structure. 11,12 It was disclosed that not only bromide but also the isobutyl group and hydride attacked epoxides in the initiation step (Scheme 2a-c). Oligomers from 1 and 3 (monomer/initiator ratio of 11.2) and the polymer from 4 in run 5 of Table 2 were analyzed by MALDI-TOF mass spectrometry.…”

Utilization of catecholic functionality in natural safrole and eugenol to synthesize mussel-inspired polymers

“…55,56 Generally, propagation via nucleophilic attacks on the less hindered methylene carbon of epoxides leads to regioregular polymers. 57,58 Optically pure (i.e. enantiopure) epoxides are thus expected to provide an easy access to isotactic polymers since the methine carbon retains its conguration (Scheme 4).…”