Isopropyl iodide → 2-Methyl-3-phenyloctan-4-one

Reaction equation

[C:1]1([CH2:7][C:8](=[O:13])[CH2:9][CH2:10][CH2:11][CH3:12])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C[O-].[Na+].I[CH:18]([CH3:20])[CH3:19]>>[CH3:19][CH:18]([CH:7]([C:1]1[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1)[C:8](=[O:13])[CH2:9][CH2:10][CH2:11][CH3:12])[CH3:20]

Participants

Reactant 3

HCID 6362Isopropyl iodide

HCID 331911-Phenyl-2-hexanone

HCID 10942334Sodium Methoxide

Product 1

HCID 598649852-Methyl-3-phenyloctan-4-one

Procedure

To an ice-cold magnetically stirred mixture of 1-phenylhexan-2-one (Intermediate II-1) (7.04 gram, 0.04 mol) and sodium methoxide (4.32 g, 0.08 mol) was added dropwise 2-iodopropane (15 ml) in a nitrogen atmosphere. The resulting mixture was heated for 1 hour at reflux temperature. The obtained mixture was allowed to attain room temperature and concentrated. The resulting residue was taken up in diethyl ether and water. The diethyl ether layer was separated and successively washed with an aqueous Na2S2O3 solution and water. The organic layer was dried over Na2SO4, filtered and concentrated. The residue was further purified using Sepacore equipment: (petroleum ether/diethyl ether=19/1 (v/v)) to give 2-methyl-3-phenyl-octan-4-one (Intermediate IIa-1) (3.52 gram) as a colorless oil; 1H-NMR (400 MHz, CDCl3) δ 0.66 (d, J=7, 3H), 0.81 (t, J=7, 3H), 0.96 (d, J=7, 3H), 1.10-1.24 (m, 2H), 1.36-1.54 (m, 2H), 2.29-2.47 (m, 3H), 3.30 (d, J=10 Hz, 1H), 7.20-7.33 (m, 5H). Rf (petroleum ether/diethyl ether=98/2 (v/v))˜0.25.