Phase transfer catalysis (PTC) generally means that the reaction between the two substances, located in totally different immiscible phases, in the presence of a catalyst. Phase Transfer catalysis is mainly used for the synthesis of organics such as pharmaceuticals, dyes, chemicals, etc. In this process, one phase acts as a reservoir of the reacting anions. The second phase, which is the organic phase, contains the organic reactants and catalysts generating lipophilic cations. The reacting anions enter the organic phase in ion pairs with lipophilic cations of the catalyst.

Now moving on to the Phase Transfer Catalyst, we will get to know about their functions and properties. But at first, come and let's know what is actually a Phase transfer catalyst means.

In chemistry, a Phase-transfer catalyst or PTC is a catalyst that facilitates the migration of a reactant from one phase into another phase where the reaction occurs.

Phase transfer catalysts have been counted as the ground-breaking strategy for setting up pragmatic conventions as for the natural synthesis, since as it offers few points regarding the interest, for example, mild reaction conditions, operational simplicity, their suitability for large‐scale synthesis, and the ecologically considerate nature of the system of reaction. Since the spearheading studies on this very enantioselective alkylations lead by chiral phase‐transfer catalysts, this exploration field has filled in as an appealing region for the quest for “green” maintainable chemistry. And a wide assortment of asymmetric changes catalyzed by the chiral onium salts as well as crown ethers has been created for the combination of significant natural compounds in the previous years.

Now moving on to the Chiral phase transfer catalyst we will look into the need of it in the asymmetric synthesis.

Chiral unnatural amino acids play a vital role in the industry of pharmaceuticals and synthesis of these are of very important significance. The asymmetric alkylation of glycine subordinates with the Chiral Phase Transfer catalysts is preferable amongst the most imperative strategies to set up the chiral unnatural amino acids. As in late, chiral phase transfer catalysts got it from cinchona alkaloids which have been a hotspot in the asymmetric catalysis. Such kind catalysts can be distributed into three generations now.

Phase-transfer catalysis has been long known as one of the versatile methods for organic synthesis. In particular, I would like to add that over more than the past three decades, asymmetric phase-transfer catalysis is based on the use of structurally well-defined chiral catalysts and has also become a topic of great scientific interest. Although various effective chiral catalysts have been reported and their many catalysts were being utilized for practical asymmetric transformations, further design and development of new chiral phase-transfer catalysts are still looking attractive research subjects in organic chemistry due to the high utility of it and practicability of phase-transfer-catalyzed reactions.

Phase-transfer catalysis has been perceived for some time as the flexible strategy for organic synthesis. Specifically, over more than the last 30 years, asymmetric phase-transfer catalysis is mainly dependent on the utilization of basically well characterized chiral catalysts which has been turned into a theme of extraordinary logical intrigue. In fact, different compelling chiral catalysts have just been reported for and these catalysts were used for practical asymmetric transformations. Additionally, the development and design of the new chiral phase transfer catalyst are still appealing research subjects in natural science because of its high utility and practicability of the phase-transfer-catalyzed responses. So by the above reasons, we can conclude and accept that the Chiral phase-transfer catalysts are a powerful tool in the asymmetric synthesis.