Syngene International Research Associate Interview Questions, Process, and Tips for Experienced

Interpretation of NMR with coupling constant

• Coupling constant is the distance between two peaks in a multiplet

• It indicates the number of neighboring protons

• The coupling constant can be used to determine the stereochemistry of a molecule

• The coupling constant can also be used to determine the hybridization of a carbon atom

• The magnitude of the coupling constant depends on the strength of the spin-spin coupling

• A doublet ha...read more

The molecule can be converted into another molecule using reducing or oxidizing agents.

• Identify the functional groups present in the molecule

• Choose a suitable reducing or oxidizing agent based on the functional groups

• Perform the reaction under appropriate conditions

• Isolate and purify the product

• Examples: converting a ketone to an alcohol using NaBH4 as a reducing agent, converting an alcohol to a ketone using PCC as an

BuLi reagent is a highly reactive and pyrophoric compound used in organic synthesis.

• BuLi should be handled under an inert atmosphere, such as nitrogen or argon.

• It should be stored in a dry and cool place, away from water and air.

• BuLi should be added slowly to the reaction mixture, with constant stirring.

• Personal protective equipment, such as gloves and goggles, should be worn at all times.

• In case of fire, use a Class D...read more

Reagents used in Suzuki coupling

• Palladium catalyst (e.g. Pd(PPh3)4)

• Organoboron compound (e.g. arylboronic acid)

• Base (e.g. potassium carbonate)

• Solvent (e.g. DMF, toluene)

Rest ethyl acetate in compound can be found by NMR using specific peaks and chemical shifts.

• Look for the peak at 1.0-1.2 ppm which corresponds to the ethyl group

• Look for the peak at 4.0-4.1 ppm which corresponds to the acetate group

• Subtract the integral of these peaks from the total integral to find the rest ethyl acetate

• Compare the chemical shifts of the peaks to known values for ethyl acetate