Onkar S. Nayal, Ph.D. (Protean Researcher)’s Post

We recently came up with an awesome idea for mitigating carbon dioxide in water that you might be interested in. https://lnkd.in/enVZCSHb

FridayFun_Mechanistic problem_08-03024

Solution: FridayFun Problem 1-03-24

A highly recommended platform for analyzing electrophilicity and nucleophilicity reactivity is available. Mayr's Database Of Reactivity Parameters https://lnkd.in/eh_zn2mw

FridayFun_Mechanistic Problem_01-03-2024 Try your hand at solving it and see if you can get it right.

HOW TO REMOVE ALDEHYDE AND REACTIVE KETONE ...... You can use a simple Liquid-Liquid Extraction Protocol to remove aldehyde and reactive ketone residue or contaminants. Add 25 mL of saturated NaHSO3(aq) to a small-scale reaction mixture, shake it for around 30 seconds, then dilute it with 25 mL of H2O. Extract the mixture with 25 mL of 10% EA/hexanes, if the desired product is not too polar.

SOME REACTION WORK-UP TRICKS Tricky Reaction Solvents: DMF or DMSO (How to remove ????) Very polar and high-boiling solvents that are difficult to remove. If your product is not dangerously polar, dilute it with lots and lots of water before extracting it with a nonpolar solvent. Rule of Thumb: For 5 mL of DMF or DMSO, use 5 X 10 mL of water during the aqueous wash. This should remove all of the DMF or DMSO. Two aqueous washes to remove DMF: 1. 5% LiCl (aq) 2. 0.5 N HCl Boc groups will survive the dilute HCl wash. TMS groups may not. Amine solvents (pyridine, di- and trialkylamines): Amines will partition into the organic layer during a typical aqueous workup. However, they become water-soluble if you 1. Wash the organic layer several times with dilute HCl solution. The protonated amine will be partitioned into the aqueous layer. For use with acid-stable target compounds only. 2. Wash the organic layer several times with 10% copper sulfate (aqueous and blue). The copper-complexed amine will partition into the aqueous solution, which turns purple. Continue to wash with the copper sulfate solution until no colour change is observed. Rule of Thumb: For 5 mL of an amine solvent, use 5 X 10 mL of the 10% aq. CuSO4 solution during the aqueous wash. This should remove all of the amine. Additional pieces of information Aqueous Solutions for Workup Mildly Acidic 1. Ammonium chloride, pH 5-6 (to neutralize) 2. 1N or 2N HCl, pH 1 (to neutralize or acidify) 3. Brine: Removes residual water from the organic layer. The last wash in every workup For Special Purposes: 1. Sodium thiosulfate (10%): to remove bromine or iodine 2.Rochelle's salt (10%): to remove aluminum salts 3. Copper sulfate (saturated): to remove amines 4. Potassium fluoride: to remove trialkyltin byproducts 5. Aqueous ammonium hydroxide/ ammonium chloride (pH 8): to remove copper (I) salts Credit goes to Not Voodoo X.4

Solution of FridayFun 24-02-2024

To do science, you need to change your perception 

Here is the FridayFun Problem 23-02-2024 can you solve It ?????