Diisopropylethylamine → 1-[6-nitro-4-oxo-3-(2-trimethylsilanyl-ethoxymethyl)-3,4-dihydro-quinazolin-2-yl]-1H-pyrazole-4-carboxylic acid ethyl ester

Participants

Reaction Steps

DIEA (4.41 mL, 25.6 mmol) was added to a suspension of 1-(6-nitro-4-oxo-3,4-dihydro-quinazolin-2-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (Intermediate from Example 164, product from Step D) (4.21 g, 12.8 mmol) in THF (64 mL), followed by (2-chloromethoxy-ethyl)-trimethylsilane (2.49 mL, 14.1 mmol). The reaction mixture was stirred at room temperature for 18 h and then concentrated. The residue was partitioned between water (75 mL) and EtOAc (75 mL), and the organic layer was washed with water (2×75 mL) and brine (50 mL), dried (MgSO4), and concentrated to yield the titled compound (5.92 g, 86% yield, 85% pure). This material was carried on to the next step without further purification. MS (ESI/Cl): mass calcd. for C20H25N5O6Si, 459.2; m/z found, 402.1 [M+H−58]+.

Provenance & Evidence