Triethyl phosphite → 1-[2-(2-Diethoxyphosphorylethoxy)ethoxy]-2-methoxy-ethane

Participants

Reaction Steps

{2-[2-(2-Methoxyethoxy)ethoxy]ethyl}iodide (6.64 g, 24.3 mmol) and P(OEt)3 (4.22 ml, 24.3 mmol) were dissolved in 1,4-dioxane (30 ml) and stirred under reflux for 24 hours. Volatiles were distilled in vacuo (150° C., 0.01 torr) to give the crude material as a thick yellow oil. Column chromatography (silica gel, EtOAc:MeOH 95:5 elution) afforded the desired product as a pale yellow oil. Yield 1.0 g, 15%. Alternative synthesis using {2-[2-(2-Methoxyethoxy)ethoxy]ethyl}iodide (5.00 g, 18.2 mmol) and P(OEt)3 (10 ml, excess) under microwave irradiation (100 W, 1 hr) gave higher yield after column chromatography (3.06 g, 10.7 mmol, 59%). 1H NMR (CDCl3, 400 MHz, 298 K): δ 4.08 (m, 4H), 3.67 (d of t, JH-P=10 Hz, JH-H=7 Hz, 2H), 3.60 (m, 6H), 3.50 (m, 2H), 3.36 (s, 3H), 2.09 (d of t, JH-P=20 Hz, JH-H=7 Hz, 2H), 1.28 (t, J=7 Hz). 13C {1H} NMR (CDCl3, 100 MHz, 298 K): δ 71.72, 70.35, 70.30, 69.97, 64.92, 61.44 (d, JC-P=6 Hz), 58.82, 26.77 (d, JC-P=138 Hz), 16.22 (d, JC-P=6 Hz). 31P{1H} NMR (CDCl3, 162 MHz, 298 K): δ 29.23. MS (FAB, m/z): 285 ([M+H]+, 100%). Exact mass found (calculated for [M+H]+, m/z): 285.15395 (285.14670).

Provenance & Evidence