>
>
Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Shweta Thakur posted an Question
January 27, 2021 • 01:31 am
![]()
30 points
30 points
- IIT JAM
- Chemistry (CY)
In my fourth step how och3 leave ....although it is a poor leaving group... r oh och h r hemio p hemiqedeu a h0 desioda ketor
Ow Oud H Catted Hemiace ble Q Lotu - T RTTest alshsl 18 etur aldekyde Reducion o stuas toAdlchde R AI Ketals oR oH OCH H R Hemio P Hemiqedeu A H0 desiodA ketor R 0d
2 Answer(s)
Answer Now
- 0 Likes
- 2 Comments
- 0 Shares
Do You Want Better RANK in Your Exam?
Start Your Preparations with Eduncle’s FREE Study Material
- Updated Syllabus, Paper Pattern & Full Exam Details
- Sample Theory of Most Important Topic
- Model Test Paper with Detailed Solutions
- Last 5 Years Question Papers & Answers
Sign Up to Download FREE Study Material Worth Rs. 500/-
Dinesh khalmaniya 1![best-answer]()
it is better leaving group so easily can remove Explanation- Good leaving groups are weak bases. Why? Think about the dissociation of an acid H–A to give H+ and A– . The species A– is the conjugate base of HA. It accepts a pair of electrons from the H-A bond. It’s a base acting in reverse. The more stable A- is, the greater the equilibrium constant will be that favors dissociation to give A- . This turns out to be the very definition of acidity! The negative log of the equilibrium constant is the familiar pKa. In other words pKa is a direct measurement of how “happy” and stable a lone pair of electrons is – the very definition of what we should be looking for when trying to quantify leaving group ability. So it should be no surprise to find that very weak bases such as halide ions (I-, Br-, Cl-) water (OH2), and sulfonates such as p-toluenesulfonate (OTs) and methanesulfonate (OMs) are excellent leaving groups. These are the conjugate bases of strong acids. (Recall that the stronger the acid, the weaker the conjugate base). [One word of caution: pKa measures an equilibrium (think “differences in energy”), whereas leaving group ability is based on reaction rates. So although the correlation is very good, it isn’t perfect.] On the other hand, strong bases are bad leaving groups. This is why alcohols don’t participate in SN2 reactions very much! the hydroxyl group (HO-) is a terrible leaving group.