4-Isopropylpyridine

4-Isopropylpyridine is a colorless to pale yellow transparent liquid with a characteristic pyridine odor at room temperature.It melts at-54.9°C and boils at 178°C.The density is 0.93 g/cm³,and the refractive index ranges from 1.4940 to 1.4970.Its flash point is 66°C.Storage under an inert atmosphere at room temperature is sufficient.The pKa of its conjugate acid is 6.02.It is slightly soluble in water but miscible with ethanol,methanol,acetone,ethyl acetate,THF,toluene,and hexane.It is stable under normal conditions but should be kept away from strong oxidants,acids,and reducers.The electron-donating isopropyl group increases the electron density and nucleophilicity of the pyridine nitrogen compared to unsubstituted pyridine.

5-Isopropylpyridine(CAS No.696-30-0)is a simple alkyl-substituted pyridine where an isopropyl group is located at the 4-position.This substitution enhances its lipophilicity and steric bulk near the nitrogen,making it a valuable ligand and solvent modifier in organometallic chemistry and separation processes.

1.Ligand in Asymmetric Hydrogenation
Acts as a monodentate ligand when coordinated to iridium or ruthenium complexes,enabling highly enantioselective hydrogenation of unsaturated carboxylic acids for producing non-steroidal anti-inflammatory drugs(NSAIDs)like ibuprofen.

2.Mobile Phase Modifier in HPLC
Used as a basic additive in reversed-phase HPLC to improve peak shape and resolution for analyzing amine-containing pharmaceuticals,suppressing undesirable silanol interactions on stationary phases.

3.Corrosion Inhibitor in Refining
Added to hydrochloric acid solutions during the acidizing of oil wells.It adsorbs onto steel surfaces,forming a protective layer that prevents corrosion by H₂S and CO₂at high temperatures and pressures.

4.Precursor for Viologen Synthesis
Quaternized to form 1-isopropyl-4,4'-bipyridinium salts,which serve as electrochromic materials in smart windows and as mediators in enzymatic biofuel cells for glucose sensing.