**2.3 Protic ethylammonium nitrate**

Crosio et al. developed a new protic ionic liquid (IL) ethylammonium nitrate (EAN) inside toluene/benzyl-n-hexadecyldimethylammonium chloride (BHDC) as shown in **Figure 5** and studied its application on reverse micelles affects [10]. They found the Cl ion nucleophilicity on the bimolecular nucleophilic substitution (SN2) reaction between this anion and dimethyl-4-nitrophenylsulfonium trifluoromethanesulfonate. It was the first study where the polar EAN was used as a suitable reaction medium for toluene-BHDC reverse micelles as a nanoreactor for performing the kinetic studies. The light scattering experiment discloses the formation of RMs containing the protic EAN ionic liquid component. Their experiments demonstrate that the homogeneous reaction medium is low effective compared to EAN-mediated SN2 reaction conditions. The protic ionic liquid EAN acts as a aprotic medium once it is entrapped in BHDC RMs by hydrogen bonding

#### **Figure 3.**

*Nucleophilic fluorination by protic ionic liquid 1a.*

#### **Figure 4.**

*Nucleophilic fluorination on secondary mesylate by using CsF and 1a.*

#### **Figure 5.** *Structures of ethylammonium nitrate (EAN).*

interactions; as a result, nucleophilicity of chloride increases dramatically. Thus, the protic EAN is found as a suitable reaction solvent for nucleophilic bimolecular substitution reactions. These experiments demonstrate the flexibility of this kind of nanoreactor system to alter the polar protic solvent trapping and its impact on the rate of the reaction.

#### **2.4 Polar protic solvent glycol**

Song et al. observed that the alcohol contained polyethylene glycol as good reaction media for various nucleophilic substitution reactions [10]. Achiral polyether derivatives have shown dramatic acceleration in the SN2 reactions by the simultaneous activation of both the nucleophile and electrophile sites of the leaving group. They also studied desiylation and found that bis-terminal ▬OH group plays a key role that the desilylative kinetic resolution is successively done of the silyl ethers of racemic secondary alcohols.
