Trifluoroacetic acid → Trifluoroacetic acid

Participants

Reaction Steps

To a suspension of diamine 248 (1.14 g, 6.80 mmol) in CH2Cl2 (10 mL) was added trimethyl orthoformate (5 mL, 46 mmol, 6.7 eq) (or any other acylating agent of choice, 6 eq) followed by TFA (0.43 mL, 5.6 mmol, 0.8 eq) and the mixture was stirred at room temperature for 2 h. Precipitate was collected by filtration, washed with CH2Cl2 and dried to afford the title compound 249 as TFA salt (1.23 g, 62% yield). 1H NMR: (CDCl3) δ (ppm): 8.57 (d, J=1.8 Hz, 1H), 8.20 (dd, J=1.8, 9.2 Hz, 1H), 8.18 (s, 1H), 7.54 (d, J=9.2 Hz, 1H), 3.94 (s, 3H). LRMS: (calc.) 177.2; (obt.) 178.1 (MH)+.

Provenance & Evidence