Water → HCID 22163774, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 1-amino-3-isopropyloxazolo[4,3-a]phthalazinium tetrafluoroborate (1.58 g) and ethyl phenylpropiolate (1.74 g) in 1,3-dimethyl-imidazolin-2-one (30 ml) was maintained at 40° C. for 19 hours and then the resulting brown solution was poured into water (200 ml), and the mixture was extracted with a mixture of petroleum ether (b.p. 40°-60° C.) and diethyl ether (1:1 v/v; 3×200 ml). The extracts were combined, dried over magnesium sulphate, and evaporated, and the resulting residue was subjected to flash chromatography on silica gel, using as eluant a mixture of petroleum ether (b.p. 40°-60° C.) and diethyl ether (19:1 v/v), to give ethyl 3-isopropyl-1-phenylpyrrolo[2,1-a]phthalazine-2-carboxylate (0.72 g) in the form of a yellow solid, m.p. 141°-142° C. [Elemental analysis: C, 77.1; H, 6.24; N, 7.8%; calculated C, 77.1; H, 6.19; N, 7.8%; NMR (in CDCl3) : 0.93 (3H, t, J=7 Hz), 1.57 (6H, d, J=7 Hz), 4.08 (2H, q, J=7 Hz), 4.35 (1H, septet, J=7 Hz), 7.23-7.50 (8H, m), 7.60-7.66 (1H, m), 8.35 (1H, s); Mass spectrum (electron impact) m/z=358].

Provenance & Evidence