N-Butyldiethanolamine → 2-(2'-Methoxycarbonylphenyl)-6-butyl[1,3,6,2]dioxazaborocan

Participants

Reaction Conditions

Reaction Steps

To a suspension of (2-methoxycarbonylphenyl)boronic acid (5.0 g, 27.8 mmol) in toluene (40 mL) was added N-butyldiethanolamine (4.8 mL, 29.2 mmol, 1.05 equiv.) via a syringe. The mixture was heated at 50° C. for two hours. After cooling to room temperature, the toluene was evaporated under reduced pressure and the remaining clear colorless crude oil was treated with heptanes (˜500 mL). The heptanes mixture was then sonicated ˜5 min and the resulting suspension was allowed to stand at room temperature overnight. The solid that precipitated was collected by filtration, washed with heptanes, and dried in a vacuum oven overnight to yield a white solid as the 2-(2′-methoxycarbonylphenyl)-6-butyl[1,3,6,2]dioxazaborocan. 1H NMR (DMSO-d6) δ: 7.55-7.59 (m, 1H), 7.17-7.29 (m, 2H), 7.12-7.14 (m, 1H), 3.85-3.92 (m, 2H), 3.78-3.82 (m, 1H), 3.78 (br. s., 1H), 3.67 (s, 3H), 3.26-3.30 (m, 1H), 3.12 (dt, J=5.2, 2.6 Hz, 2H), 3.03-3.11 (m, 2H), 2.41-2.49 (m, 4H), 1.45-1.55 (m, 2H), 0.98-1.05 (m, 2H), 0.83 (s, 1H), 0.71-0.77 (m, 3H). Amount obtained, 8.3 g, (98.1% yield).

Provenance & Evidence