1-(2,6-dichlorophenyl)-5-(2-chlorophenyl)-7-(1,4-dioxaspiro(4.5)dec-7-ene-8-yl)-3,4-dihydro-2(1H)-quinazolinone → 1-(2,6-Dichlorophenyl)-5-(2-chlorophenyl)-7-(1,4-dioxaspiro(4.5)dec-8-yl)-3,4-dihydro-2(1H)-quinazolinone

Participants

Reaction Steps

To 1-(2,6-dichlorophenyl)-5-(2-chlorophenyl)-7-(1,4-dioxaspiro(4.5)dec-7-ene-8-yl)-3,4-dihydro-2(1H)-quinazolinone (818.8 mg, 1.51 mmol) (INTERMEDIATE 71) in ethyl acetate (25 mL) under a nitrogen atmosphere was added platinum oxide (Adam's catalyst, 164 mg). The reaction mixture was purged with H2 (via balloon) and stirred for 2 hours. Proton NMR analysis of an aliquot showed incomplete reduction. An additional 82 mg of PtO2 was added and the solution stirred under a H2 atmosphere for another hour. The reaction mixture was filtered over Celite, rinsed with 10% MeOH in DCM and concentrated. The crude material purified by silica gel chromatography eluting with 1% MeOH in DCM to give 1-(2,6-Dichlorophenyl)-5-(2-chlorophenyl)-7-(1,4-dioxaspiro(4.5)dec-8-yl)-3,4-dihydro-2(1H)-quinazolinone. 1H NMR (CDCl3, 500 MHz): selected data δ 1.61 (m, 4H), 1.78 (m, 4H), 2.38 (m, 1H), 3.92 (m, 4H).

Provenance & Evidence