Diisopropylethylamine → (R)-3-(3-(4-phenoxyphenyl)ureido)-4-(trimethylammonio)butanoate

Participants

Reaction Steps

To a solution of (R)-aminocarnitine (27 mg, 0.17 mmol) and diisopropylethylamine (88 uL, 0.51 mmol) in MeOH (2 mL) was added 1-isocyanato-4-phenoxybenzene (71 mg, 0.34 mmol) and the reaction stirred for 18 h. The MeOH was removed in vacuo and the residue stirred with 1:1 ether/EtOAc. Impurities were dissolved in the ether/EtOAc and discarded and the remaining material was taken up into 90:10 CH2Cl2/MeOH and then loaded onto a short SiOH plug. The title compound was eluted by increasing MeOH content in 10% steps to 60%. The compound was then taken up into 90:10 CH2Cl2/MeOH and filtered through a plug of celite which gave after drying the title compound as a white powder (10 mg, 16%). 1H NMR (400 MHz, CD3OD) δ 7.37-7.30 (m, 4H), 7.07 (t, 1H, J=7.2 Hz), 6.95-6.92 (m, 4H), 4.73-4.71 (m, 1H), 3.80-3.54 (m, 2H), 3.26 (s, 9H), 2.81-2.68 (m, 2H); MS ESI 372.2 [M+H]+, calcd for [C20H25N3O4+H]+ 372.43.

Provenance & Evidence