N,N,N',N',N'',N''-Hexamethylmethanetriamine → Benzyl 10-((dimethylamino)methylene)-9-oxo-3-azaspiro[5,5]undec-7-ene-3-carboxylate

Participants

Reaction Steps

9-oxo-3-aza-spiro[5.5]undec-7-ene-3-carboxylic acid benzyl ester, Preparation I-IA-2 (15.2 g, 51 mmol) was dissolved in 180 mL toluene and tris(dimethylamino)methane (22.2 g, 27 mmol) was added. The reaction was heated to reflux for 5 hours and then allowed to cool to room temperature overnight. The reaction solution was concentrated in vacuo to provide the title compound (18.0 g, 100%): +APCI MS (M+H) 354.6; 1H NMR (400 MHz, CDCl3) δ ppm 7.49 (s, 1 H), 7.28-7.40 (m, 5 H), 6.59 (d, J=10.16 Hz, 1 H), 6.01 (d, J=9.97 Hz, 1 H), 5.13 (s, 2 H), 3.52-3.66 (m, 2 H), 3.39-3.52 (m, 2 H), 3.07 (s, 6 H), 2.74 (s, 2 H), 1.58-1.73 (m, 2 H), 1.41-1.58 (m, 2 H).

Provenance & Evidence