Novel non-ionic surfactants synthesised through the reaction of CO2 with long alkyl chain epoxides

Hydrophobically-enhanced “on water” cycloaddition of CO2to long-chain terminal epoxides

“…11,19,34 Concerning the observed evolution of the initial miniemulsion into a coarse emulsion, this is attributed to the formation of LC-CCs, which are also known to be surface active. 7 Indeed, we observed a decrease of the interfacial tension between a mixture of epoxide and cyclic carbonate and water by increasing the molar ratio between carbonate and epoxide (see Table S3, ESI †). After a certain epoxide conversion, the amount of non-ionic cyclic carbonate adsorbing on the surface of the emulsion droplets, and hence competing with the adsorption of DDA, is sufficient to destabilize the original emulsion (see Fig.…”

“…entries 5 and 7). The use of water/TBAI as a catalyst for the cycloaddition of CO 2 to 1a was previously reported 7 by Pescarmona et al but under harsher conditions (90 °C, 10 bar) with a much lower water/epoxide ratio (1 : 184) with catalytic amounts of water acting as H-bond donor 16 a ,24 and the reaction taking place in the bulk epoxide phase. Therefore, we performed the target reaction using the latter water/epoxide ratio but under the milder conditions used in this study (entry 8) observing only very low 1a conversion to 2a .…”

“…4 b ,5 In this context, long-chain aliphatic terminal LC-CC have received increasing attention, as monomers for the preparation of non-isocyanate polyurethanes 6 and non-ionic surfactants. 7 It is therefore attractive to investigate practical, milder and readily accessible methods to prepare LC-CC which do not require sophisticated and expensive catalytic systems or pressurized equipment. Indeed, working under atmospheric CO 2 pressure is operationally simpler and, in the large scale, avoids the energy intensive recompression of CO 2 .…”

“…11,19,34 Concerning the observed evolution of the initial miniemulsion into a coarse emulsion, this is attributed to the formation of LC-CCs, which are also known to be surface active. 7…”

Organocatalytic Polymers from Affordable and Readily Available Building Blocks for the Cycloaddition of CO2 to Epoxides

“…Finally, The Journal of Organic Chemistry pubs.acs.org/joc Perspective long-chain cyclic carbonates display a surface activity that may hinder the access of less surface-active reagents (epoxide) to the surface of the catalytic support. 260 A more marked difference in catalytic performance is observed when comparing the polymeric catalysts discussed above with their nonporous counterparts. Nevertheless, the latter retain a significant catalytic activity despite having extremely low surface areas.…”