Click Chemistry – Azide-Alkyne Cycloaddition

Nowadays click chemistry becomes a trending topic because of the trio who won the noble prize in chemistry this year. As it becomes a trending topic then there a high chance that questions are asked from this topic. The questions from this topic can be considered as a Current Affair question or one can identify this as a Chemistry question. This article will helps SSC, Banking, UPSC and Railway aspirants to score more in exams. Kindly bookmark this article for your future reference.

What is Click Chemistry :

• Barry Sharpless and colleagues coined the phrase “Click Chemistry” in 2001 to refer to extremely efficient and selective reactions that primarily rely on the creation of carbon-hetero bonds. The name “Click” implies that molecules can be connected just as quickly as mechanical fasteners.
  
• By using a few useful and dependable reactions, click chemistry is a more recent method for creating compounds that are similar to drugs and can quicken the drug development process.
  
• According to Sharpless and colleagues, a click reaction is one that is broad in scope, simple to carry out, employs only easily accessible chemicals, and is unaffected by oxygen and water. In reality, water is frequently the greatest reaction solvent, offering the highest yields and rates.

Characteristics of “Click Chemistry” :

• Easy purification by nonchromatographic techniques, 
• Stereospecific but not necessarily enantioselective, 
• Oxygen and water insensitive, 
• Easy reaction conditions,
• Easily accessible building blocks, 
• Rapid reaction speeds, 
• Robust reactions with extremely high yields, 
• No or only benign organic solvents

Classification of Click Reactions :

The term “click chemistry” refers to a collection of potent linking reactions that are easy to carry out, have high yields, call for little to no purification, and may attach a variety of structures without the need for additional protective procedures. There are now four main categories for Click reactions :

• Nucleophilic substitution reactions.
• Cycloaddition of unsaturated compounds.
• Carbonyl reactions of the non-aldol type.
• Additions to carbon-carbon multiple bonds.

Why this is in News nowadays:

This time it is news because of a trio who won the noble prize in chemistry. Let’s talk about these scientist ones by one.

1. Carolyn Bertozzi :

• Born on October 10, 1966, Carolyn Ruth Bertozzi is an American scientist and Nobel laureate who is renowned for her extensive work in both biology and chemistry.
  
• She came up with the phrase “bioorthogonal chemistry” to describe chemical processes that work well with living things.
  
• Her most recent work includes the manufacture of chemical instruments to investigate the role of glycans, which are sugars found on cell surfaces, in conditions including cancer, inflammation, and viral infections like COVID-19.
  
• She now holds the Anne T. and Robert M. Bass Professorship in the School of Humanities and Sciences at Stanford University. In addition, Bertozzi is a researcher at the Howard Hughes Medical Institute (HHMI) and the former director of the Molecular Foundry, a lab at the Lawrence Berkeley National Laboratory dedicated to nanoscience research.
  
• At the age of 33, she was given the MacArthur “genius” prize. She was the first female recipient of the esteemed Lemelson-MIT Prize faculty award in 2010.
  
• She is a 2005 National Academy of Sciences, 2011 Institute of Medicine, and 2016 National Academy of Inventors member (2013).
  
• The American Chemical Society’s first peer-reviewed open-access journal, ACS Central Science, which makes all of its material available for free to the public, announced in 2014 that Bertozzi will serve as its editor.
  
• She has belonged to the Accademia dei Lincei since 2021. Bertozzi has served as an inspiration to students and coworkers as an out lesbian in science and academia.

2. Morten P. Meldal :

• Danish scientist Morten Peter Meldal was born on January 16, 1954. At the University of Copenhagen in Copenhagen, Denmark, he teaches Chemistry.
  
• The CuAAC-click reaction developed concurrently with but independently of Valery V. Fokin and K. Barry Sharpless is his most famous invention.
  
• Technical University of Denmark (DTU) awarded Meldal a B.S. and a Ph.D. in Chemical Engineering; his Ph.D. work, which was under Klaus Bock’s direction and concentrated on the synthesis of oligosaccharides, was in this field.
  
• He worked as a freelance research associate in organic chemistry at DTU and the University of Copenhagen from 1983 to 1988.
  
• He worked as a postdoctoral research associate at the Medical Research Council Center’s Laboratory of Molecular Biology at Cambridge University’s postdoctoral years of 1985 and 1986.

3. Karl Barry Sharpless :

• American scientist Karl Barry Sharpless, a two-time winner of the Chemistry Nobel Prize, is renowned for his work on stereoselective reactions and click chemistry.
  
• Sharpless was born in Philadelphia, Pennsylvania, on April 28, 1941. 
  
• For his work on chirally catalyzed oxidation processes, Sharpless received half of the 2001 Nobel Honor in Chemistry, and he shared a third of the prize in 2022 with Carolyn R. Bertozzi and Morten P. Meldal “for the creation of click chemistry and bioorthogonal chemistry.
  
• Sharpless taught at Stanford University and the Massachusetts Institute of Technology (1970–1977, 1980–1990). (1977–1980).
  
• Sharpless developed Sharpless asymmetric epoxidation, which was utilized to create (+) – disparlure when he was a student at Stanford.

Why this is called as Azide-Alkyne Cycloaddition :

Copper ions enhance the reaction between azides and alkynes. Today, people all around the world employ this process to quickly connect molecules together.