Bromoform → (2,2-Dibromocyclopropyl)benzene

Temperatur

25 °C

In a 1 liter 3-neck flask, bromoform (312 g, 1.23 mol) was added dropwise over 120 min to stirred solution of styrene (100 g, 0.96 mol), benzyltriethylammonium chloride (7 g, 0.031 mol) and powdered potassium hydroxide (80.6 g, 1.44 mol) in dichloromethane (480 mL) at 40° C. The mixture was stirred at 25° C. for 20 h. The reaction mixture was filtered through a short plug of silica and the filtrate was concentrated. The dark residue was distilled at 80° C. under reduced pressure (about 50 Pa) to give the desired product as pale yellow liquid (233 g, yield 88%, purity 98% by HPLC(UV)). 1H NMR (CDCl3, 400 MHz): δ 7.38˜7.42 (m, 3H), 7.29˜7.31 (m, 2H), 2.98˜3.03 (m, 1H), 2.15˜2.20 (m, 1H), 2.04˜2.08 (m, 1H).

1. filtrationThe reaction mixture was filtered through a short plug of silica
2. concentrationthe filtrate was concentrated
3. distillationThe dark residue was distilled at 80° C. under reduced pressure (about 50 Pa)

ORD-Eintrag

ord-68733d94166f485990519797662af204

Quelldatensatz

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08283454B2