2-Tert-Butylphenol → 2-[4-(2-tert-butyl-phenoxy)-6-oxo-6H-pyridazin-1-yl]-3-cyclopentyl-propionic acid

Participants

Reaction Steps

In an analogous manner to the stepwise sequence outlined in intermediate 19, starting from 4,5-dichloro-2-(tetrahydropyran-2-yl)-2H-pyridazin-3-one (Intermediate 20) and 2-tert-butyl-phenol and alkylating with 2-bromo-3-cyclopentyl-propionic acid methyl ester (Intermediate 10) afforded 2-[4-(2-tert-butyl-phenoxy)-6-oxo-6H-pyridazin-1-yl]-3-cyclopentyl-propionic acid as a white solid (13.2 g, 81% for the final step); LC-MS 385.2 [M+1]+, tR=5.86 min. Purity on HPLC: 95.7% (214 nm), 88.8% (254 nm), tR=7.87. 1H NMR (300 MHz, CDCl3): δ 10.85 (s, 1H), 7.83 (m, 1H, J=2.4 Hz), 7.44 (d, 1H, J=4.5 Hz), 7.20 (m, 2H), 6.97 (d, 1H, J=7.5 Hz), 6.06 (d, 1H, J=2.4 Hz), 5.36 (dd, 1H, J1=9.6 Hz, J2=4.2 Hz), 2.33˜2.20 (m, 1H), 2.20˜2.05 (m, 1H), 1.66˜1.14 (m, 7H), 1.33 (s, 9H), 1.17˜1.05 (m, 2H).

Provenance & Evidence