1-(2-Hydroxyethyl)-2,3,3-trimethyl-3H-indolium iodide synthesis

Yield:50839-66-2 92%

Reaction Conditions:

in ethanol; for 12 h;Reflux;

Steps:

Synthesis of 2,3,3-trimethyl-N-(2-hydroxylethyl)-indolenine (1).

1 mL of 2,3,3-trimethyl-indolenine. (6.3 mmol) and 0.49 mL of 2-indoethanol (6.3 mmol) were initially added into a flask. 5 mL of ethanol was then added into the flask as the solvent. The system was then heated to reflux for 12 hours to complete the reaction. After cooled down to room temperature, the mixture was poured into 100 mL of petroleum ether. The system was then filtered and washed with petroleum ether for 3 times. The final product was obtained as purple powder, in 92% yield. ¹H NMR (400 MHz, DMSO-d₆), δ (ppm): 7.98-7.95 (m, 1H), 7.87-7.85 (m, 1H), 7.65-7.61 (m, 2H), 5.23 (s, 1H), 4.61 (t, J = 5.3 Hz, 2H), 3.89 (t, J = 5.2 Hz, 2H), 2.83 (s, 3H), 1.56 (s, 6H).

References:

He, Xiuquan;Tian, Minggang;Yang, Rui;Yu, Xiaoqiang;Zhang, Huamiao [Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy,2021,vol. 246,art. no. 119035] Location in patent:supporting information