Organocatalyzed Synthesis of Oleochemical Carbonates from CO₂ and Renewables

Abstract

Bifunctional phosphorus-based organocatalysts proved to be highly efficient for the atom-economic reaction of CO and epoxidized oleochemicals. Notably, those products are obtained from CO and renewable feedstocks only. Structure-activity relationships have been deduced from a screening of 22 organocatalysts in a test reaction. Bifunctional catalysts based on a phosphonium salt bearing a simple phenolic moiety proved to be extraordinarily active under comparatively mild and solvent-free reaction conditions. In the presence of the most active organocatalyst 12 oleochemical carbonates were isolated in excellent yields up to 99 %. This organocatalyzed reaction represents an excellent example for the realization of the 12 Principles of Green Chemistry as well as the 12 Principles of CO Chemistry.

An Efficient and Versatile Lanthanum Heteroscorpionate Catalyst for Carbon Dioxide Fixation into Cyclic Carbonates

“…Microanalyses were carried out with aP erkinElmer 2400 CHN analyzer. 1 H, and 13 CNMR spectra were recorded on aV arian Inova FT-500 ( 1 HNMR: 500 MHz; 13 CNMR:1 25 MHz) spectrometer and referenced to the residual deuterated solvent. The NOESY-1D spectra were recorded with the following acquisition parameters:i rradiation time:2 s; number of scans:2 56, by using standard Varian-FT software.…”

“…In view of the high activity and broad substrate scope of the 1/TBAB catalyst system for the synthesis of cyclic carbonates from epoxides and carbon dioxide, we focused our attention on the synthesis of ar ange of bio-derived cyclic carbonates, which to dateh ave received very little attention (Figure 3). [13] Almost quantitative conversionst of uran-based cyclic carbonates 4a and 4b were achieved after 4h at 70 8Ci nt he presence of 0.05 mol %o ft he catalysts ystem. Bio-based cyclic carbonates 4c-e,d erived from the diacids succinic acid, fumaric acid, and glutarica cid, were isolated in excellent yields with high selectivities (> 99 %) after 16 h. These cyclic carbonates are particularly interesting, owing to the possibility of using them as buildingb locks for the synthesis of non-isocyanate polyurethanes by the reaction of bis-cyclic carbonates with diamines.…”

“…The catalytic activity was shown to be optimal at 110 8C, giving an initial TOF of 8500 h À1 per metal centeri nt he presence of 0.003 mol %o fc omplex 1.T os tudy the effect of the reaction time on the initial TOF value, reactions were carried out with times of 0. 5,1,1.5,2,4,6,and 10 h( Ta ble S2,entries 4,[9][10][11][12][13][14], showingt hat the initial TOF remained unchanged after 2h and slowly decreasedf or longer reaction times.W hen the catalyst loading and reactiont ime were fixed at 0.0003mol %a nd 2h,9 %c onversion of styrene oxide into styrenec arbonate was achieved with aT OF of 15 000 h À1 at 110 8C( Ta ble S2, entry 15). Under these reaction conditions, the TON value reached3 06 667 after 48 h, indicating that the catalyst is stable during the reaction.…”

Plasma‐Assisted Immobilization of a Phosphonium Salt and Its Use as a Catalyst in the Valorization of CO2

“…Bifunctional phosphonium salts bearing a hydroxyl group in the 2‐position proved to be a superior structural motif in the cycloaddition of CO 2 and epoxides to form cyclic carbonates . We envisioned that an allyl substituent might allow subsequent immobilization in an a‐C:H thin film generated by plasma techniques.…”

“…Bifunctional phosphonium salts bearing ah ydroxyl group in the 2-position proved to be as uperior structuralm otif in the cycloaddition of CO 2 ande poxides to form cyclic carbonates. [23] We envisioned that an allyl substituent might allow subsequent immobilization in an a-C:H thin film generated by plasma techniques. Thus, bifunctional phosphonium salts 5a and 5b were synthesized by allylation of 2-(diphenylphospha-nyl)phenol( 3)w ith allyl bromide (4a)a nd allyl iodide (4b), as shown in Scheme 1a.T he incorporationo f5a and 5b into the a-C:H films most probably leads to as aturated linkagei nt he immobilized catalyst 6 (Scheme 1b).…”