Isobutylene → HCID 70495900, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 4-amino-benzoic acid methyl ester (8.25 g, 50 mmol) and 3-formyl-benzoic acid methyl ester (9.03 g, 55 mmol) in acetonitrile (200 mL) were added isobutene (14 mL, 200 mmol) and ytterbium(III) trifluoromethanesulfonate (Yb(OTf)3) (4.65 g, 7.5 mmol). The resulting mixture was stirred at 90° C. for 16 h in sealed tube. The mixture was diluted with ethyl acetate (300 mL) and washed with water (100 mL×2) and brine (100 mL×2) and then dried over anhydrous sodium sulfate. The solvent was removed in vacuo and the residue was purified by ISCO combi-flash chromatography (gradient elution, 10-50% ethyl acetate in petroleum ether) to afford 2-(3-methoxycarbonyl-phenyl)-4,4-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethyl ester (8 g, 43%) as a light yellow solid: MS (ESI) M+1=368.2.

Provenance & Evidence