Synthesis of Monoalkyl Glyceryl Ethers by Ring Opening of Glycidol with Alcohols in the Presence of Lewis Acids

Abstract

The present work deals with the production of monoalkyl glyceryl ethers (MAGEs) through a new reaction pathway based on the reaction of glycidol and alcohols catalyzed by Lewis acid-based catalysts. Glycidol is quantitatively converted with high selectivity (99 %) into MAGEs under very mild reaction conditions (80 °C and 0.01 mol % catalyst loading) in only 1 h using Al(OTf) or Bi(OTf) as catalyst. The proposed method enhances the choice of possible green synthetic approaches for the production of value-added products such as MAGEs.

First Attempt of Glycidol‐to‐Monoalkyl Glyceryl Ethers Conversion by Acid Heterogeneous Catalysis: Synthesis and Simplified Sustainability Assessment

“…[38] GO and sulfonated charcoal produce MAGEs selectively but with low productivity owing to their lower acidity (Table 1, see entries 11 and 5). [14] To evaluatet he potential reuse of the spent catalysta nd to maximize the heterogeneous catalysis advantages,t he best catalysts (i.e.,N afion, sulfonated silica, and supported metal triflates)a re removed by filtration of the reactionm ixture, washed with ethanol, dried overnight at room temperature, and then reusedasecond time for MAGEs synthesis. [40] In the presence of M-K10, am oderate conversion and al ow selectivity to MAGEsi so bserved owing to glycidol oligomerization (Table 1, entry 2).…”

“…MAGEsh ave been also synthesized by glycerol etherification with n-butanol( 150 8C, 6.5 mol %B i(OTf) 3 as catalyst, 24 h) and 1-dodecanol (130 8C, 1equivcetyltrimethylammonium bromide (CTAB) and 10 wt %o fH + as catalysts,2 4h)i nt he presence of homogeneous catalysts with good yields (70 %a nd 60 %r espectively). [11] Only af ew studies have reported the preparation of MAGEs startingf rom glycidol [8,[14][15][16] and, in this context,M AGEs have been obtained with high selectivity by using homogeneous catalysts and very preliminary results have been reported in the presence of heterogeneous basic catalysts (71 %w /w toward glycidol with Amberlyst IRA-400). [8,35] Generally,t his approachp ermitsM AGEst ob eo btained with high selectivity,f avoring the developmento fs olvents,i nm ostc ases with av ery low eco-toxicity [36] and with tunable properties.…”

“…[33,34] Industrial building blocks, alternative to glycerol, have been successfully used to prepareM AGEs, such as glycidol, epichlorohydrin, allyl alcohol, and 3-chloro-1,2-propanediol. [16] In our previousstudies, [14,15] we reported the selectivepreparation of MAGEs under mild reactionc onditions (80 8C, 0.01 mol %c atalyst, alcohol/glycidol 9:1m olarr atio, 1h), by Scheme1.Investigated routes for the synthesis of glycidol. [11] Only af ew studies have reported the preparation of MAGEs startingf rom glycidol [8,[14][15][16] and, in this context,M AGEs have been obtained with high selectivity by using homogeneous catalysts and very preliminary results have been reported in the presence of heterogeneous basic catalysts (71 %w /w toward glycidol with Amberlyst IRA-400).…”

“…[8] MAGEsa re high-value compounds with severali ndustrial applications in the field of cosmetics,p harmaceuticals, solvents, andd etergents. [8,[14][15][16] Furthermore,g lycidol is a very reactive molecule employeda lso for the production of severalinteresting compounds (diols, organic carbonates, pharmaceuticals, polymers, etc.) [12,13] Glycidol was also recently recognizeda sa ni nteresting and valuable starting chemicalt op roduce MAGEs.…”

Glycidol, a Valuable Substrate for the Synthesis of Monoalkyl Glyceryl Ethers: A Simplified Life Cycle Approach

“…[23] The results showedt hat at emperature of 80 8C, an alcohol/glycidol molar ratio of 9:1, and 0.01 mol %o fA l(OTf) 3 were necessary to convert glycidol with high selectivity to MAGEs in 1h,l imiting the production of glycidol oligomers. [23] The results showedt hat at emperature of 80 8C, an alcohol/glycidol molar ratio of 9:1, and 0.01 mol %o fA l(OTf) 3 were necessary to convert glycidol with high selectivity to MAGEs in 1h,l imiting the production of glycidol oligomers.…”