Synthesis of Fluorinated Dialkyl Carbonates from Carbon Dioxide as a Carbonyl Source

Abstract

Fluorinated dialkyl carbonates (DACs), which serve as environmentally benign phosgene substitutes, were produced successfully from carbon dioxide either directly or indirectly. Nucleophilic addition of 2,2,2‐trifluoroethanol to carbon dioxide and subsequent reaction with 2,2,2‐trifluoroethyltriflate (3 a) afforded bis(2,2,2‐trifluoroethyl) carbonate (1) in up to 79 % yield. Additionally, carbonate 1 was obtained through the stoichiometric reaction of 3 a and cesium carbonate. Although bis(1,1,1,3,3,3‐hexafluoro‐2‐propyl) carbonate (4) was difficult to obtain by either of the above two methods, it could be synthesized through the transesterification of carbonate 1.

Neighboring Group Participation and Internal Catalysis Effects on Exchangeable Covalent Bonds: Application to the Thriving Field of Vitrimer Chemistry

“…The exchange between nitrophenylcarbonates and phenol was twice faster with the ortho-substituted carbonate than with the para-substituted homologue (Figure c). Similarly, bis­(trifluoroethyl)­carbonates were shown to exchange with various alcohols and phenols in refluxing heptane or toluene (at 98 and 111 °C, respectively) in the presence of a base, , and their reactivity was reported to be between the very reactive dimethylcarbonate and the less reactive diphenylcarbonate (Figure d) …”

“…Similarly, bis-(trifluoroethyl)carbonates were shown to exchange with various alcohols and phenols in refluxing heptane or toluene (at 98 and 111 °C, respectively) in the presence of a base, 225,228 and their reactivity was reported to be between the very reactive dimethylcarbonate and the less reactive diphenylcarbonate (Figure 13d). 229 Kamps et al studied bis(methylsalicyl)carbonate (BMSC, Figure 14) as an activated carbonate to lower the temperature for melt transcarbonation synthesis of polycarbonate. 227 BMSC was polymerized with bisphenol A (BPA), and this polymerization was compared to that of diphenylcarbonate (DPC) and BPA.…”

“…(c) Polymerization rate of nitrophenylcarbonates with bisphenol A depending on the substituent position 226. (d) Effect of CF 3 substituent on the exchange rate 229.…”

Photo-on-Demand Base-Catalyzed Phosgenation Reactions with Chloroform: Synthesis of Arylcarbonate and Halocarbonate Esters

“…However, its high toxicity hinders its convenient use in organic synthesis in both academic and industrial settings. To overcome this problem and the environmental concerns of phosgene, halocarbonate esters are expected to be phosgene substitutes …”

“…For these reasons, the halocarbonate esters are expected to extend the replacement of the phosgenation reactions . There are, however, some essential problems: both the halocarbonate esters and arylcarbonate esters are themselves synthesized with COCl 2 , whose high reactivity allows reaction with acidic alcohols having low nucleophilicity. , Furthermore, industrial production of DPC is attained through multistep syntheses starting from CO 2 and ethylene oxide (EO), which also exhibits high toxicity and explosibility . This background motivated us to develop a simple safe method of synthesizing reactive carbonate esters .…”