## 2 Applications in Chemistry
### Substitution Reaction  
Cyclic carbonates can be used to prepare new organochalcogen derivatives. The interest in compounds containing sulfur, selenium, and tellurium atoms has been continuously increasing, due to their potential applications as synthons for the synthesis of heterocycles [52], in cross-coupling reactions [53; 54], and in asymmetric synthesis [55; 56]. Those compounds have applications in materials science [57; 58; 59], and as key intermediates in the synthesis of natural products [60; 61; 62]. [PERSON] and co-workers [63] recently reported the synthesis of 4-arylsulfanylmethyl-1,3-dioxolan-2-ones under microwave irradiation (MW) using an environmentally benign KF/Al\({}_{2}\)O\({}_{3}\)/PEG-400 system [64]. By applying KF/Al\({}_{2}\)O\({}_{3}\) as an efficient heterogeneous base, 3-O-toosyl glycerol 1,2-carbonate **1h** (TGC) reacted with alkyl, aryl, or heteroaryl thiols **17** to provide good yields of the corresponding sulfanylated carbonates **1** after short times of MW irradiation at 60 \({}^{\circ}\)C. This green methodology was extended to thiophenols bearing either electron-donating (CH\({}_{3}\)) or electron-withdrawing groups (Cl and F) in the _para_- and _ortho_-positions, to provide with good yields the respective 4-arylthio-1,2-glycerol carbonates. However, when the strong electron-donating amino group was present in the _ortho_-position (2-aminobenzenenthiol), only 65% yield of the desired product was obtained, due to the disfavoring proton abstraction from the thiol (Scheme 16). The conversion was extended, albeit in lower yields, to 2-mercaptoethanoldiazolyl and dodecyl derivatives. The possibility of developing a selective method for the synthesis of 1,3-bis-arylthiopropan-2-ols **18** by incorporation of two thiol units was explored (Scheme 17). By reacting a second equivalent of thiol **17** under 15 h conventional heating at 90 \({}^{\circ}\)C, the corresponding disubstituted products **18** were obtained in good to excellent yields. When conducted at 90 \({}^{\circ}\)C for 3 h in a microwave reactor (irradiation power of 200 W), the same compounds **18** were isolated in slightly lower yields [63]. The same year, [PERSON]'s group reported the selective synthesis under stoichiometric control of 4-chalcogenomethyl-1,3-dioxolan-2-ones and 1,3-bis(organylchalcogenyl)propanamide-ols [46]. To obtain the GC-derived chalcogenoheres **1**, diaryl diselenides **19** or disulfides **20** (0.6 equivalent) were first reduced using NaBH4/PEG-400 under inert atmosphere, before the addition of TGC **1h** (Scheme 18). A library of eleven compounds **1** was prepared with 55-92% yield after 2 h reaction at 50 \({}^{\circ}\)C. The protocol was extended to aliphatic diselenides, and when dibutyl diselenide was used, the corresponding selenide was isolated with 74% yield. In general, diaryl disulfides lead to better yields when compared to the seleno-analogues. During the optimization process, it was observed that increasing the amount of diaryl diselenides **19** or disulfides **20** to 1.2 equivalent led to ring-opening of the carbonate unit of **1h** over 1 h, resulting in symmetrical and unsymmetrical 1,3-bis(organochalcogenyl)propanamide-ols **18** in moderate to excellent yields (Scheme 19). The reaction works well when either electron-donating or electron-withdrawing groups are present in the aromatic unit R. It is worth noting that when using dimesityl diselenide in the synthesis of symmetrical compounds **18**, 3 h reaction was needed to reach 94% yield of the expected product. Moreover when using 1,2-bis(2-chlorophenyl)disulfide in the synthesis of unsymmetrical compounds **18**, the respective product was isolated with 40% yield after 1 h reaction. The stereoselective construction of cyclic carbonate systems is another attractive line of studies that has been explored.