A green solvent approach to the chemistry of 1,2‐diaryl‐1,2‐disodioethanes

Abstract

We investigated the generation and the reactivity of selected 1,2‐diaryl‐1,2‐disodioethanes employing cyclopentyl methyl ether and 2‐methyltetrahydrofuran as green solvent alternatives to tetrahydrofuran. Both solvents proved suitable for the generation of these vic‐diorganometals, as well as for their employment as single‐electron transfer reagents. On the other hand, 2‐methyltetrahydrofuran appears as the solvent of choice in reactions involving the employment of these diorganometals as nucleophiles or bases. Accordingly, our results disclose an environmentally more sustainable approach to the chemistry of these diorganometals and, in a wider sense, to reductive metalation reactions. Copyright © 2012 John Wiley & Sons, Ltd.

Chemoselective CaO‐Mediated Acylation of Alcohols and Amines in 2‐Methyltetrahydrofuran

“…[30] Evidently, an organic process performed in a toxic solvent, Et 2 O, does not meet the strict safety requirements of pharmaceutical industry applications and the search for alternative, non-contaminating solvents is of great importance. [31] Therefore, in recent years we [32][33][34][35] and others [36][37][38][39][40] have demonstrated the beneficial effect of replacing ether-type solvents with biomass-derived (corncobs or bagasse) solvents such as 2-methyltetrahydrofuran (2-MeTHF). [41] We observed a signifi-cant improvement when switching from Et 2 O to 2-MeTHF; maximizing the reaction yield to 97 % (entry 6).…”

Recent advancements on the use of 2-methyltetrahydrofuran in organometallic chemistry

“…Azzena reported that the generation and reactivity of single-electron transfer reagents such as 1,2-diaryl-1,2-disodioethanes is best accomplished in 2-MeTHF in alternative to THF [57]. Solution of this dianion in 2-MeTHF proved to be stable under dry Ar in a refrigerator for at least 24 h. Their results suggest that the employment of 2-MeTHF as a solvent promotes the nucleophilic substitution pathway of 1,2-diaryl-1,2-disodioethanes with 1,3-dichloropropane to a higher extent.…”

Reducing properties of 1,2-dipyridyl-1,2-disodioethanes: chemical validation of theoretical and electrochemical predictions

“…Besides applications as dinucleophiles in the diastereoselective synthesis of trans-1,2-diarylcyclopentanes 9 and borinanes, 10 we previously described their use as electron-transfer reagents for highly effective reductive eliminations in 1,2-hetero-disubstituted compounds 11,12 and degradations of aromatic persistent organic pollutants. [13][14][15][16][17] A comparison between the electroreduction potentials of the 1,2-diarylethenes and the results obtained for the reduction of model compounds with the corresponding 1,2-diaryl-1,2disodioethanes bearing different substituents allowed us to observe that the less delocalized dianions are the most powerful reducing agents, and vice versa. 18 These results were substantiated by establishing that the outcome of the reactions between halogenated arylacetic acids and 1,2-diaryl-1,2disodioethanes strongly depends on the nature of both partners.…”