Carbon tetrabromide → 4-(Bromomethyl)-1,1-difluorocyclohexane

Temperature

0 °C

(4,4-Difluorocyclohexyl)methanol (7.22 g, 48.08 mmol) and triphenylphosphine (25.2 g, 96.16 mmol) were dissolved in DCM (75 mL) and cooled to 0° C. under nitrogen atmosphere. Carbon tetrabromide (31.9 g, 96.16 mmol) was dissolved in DCM (75 mL) and added to the reaction mixture. The mixture was stirred at room temperature overnight. The solvent was evaporated. Pentane (250 mL) was added to the orange residue, which caused triphenylphosphineoxide to precipitate. The off-white solids were filtered off. The filtrate was evaporated and purified on a ISOLUTE Silica Flash column (50 g). Pentane followed by EtOAc:pentane (1% EtOAc) was used as eluent. 4-(Bromomethyl)-1,1-difluorocyclohexane (5.48 g, 54%) was isolated. 1H NMR (400 MHz, cdcl3) δ 1.32-1.46 (m, 2H), 1.64-1.84 (m, 3H), 1.90-1.99 (m, 2H), 2.05-2.18 (m, 2H), 3.31 (d, 2H).

1. additionadded to the reaction mixture
2. customThe solvent was evaporated
3. additionPentane (250 mL) was added to the orange residue, which
4. customto precipitate
5. filtrationThe off-white solids were filtered off
6. customThe filtrate was evaporated
7. custompurified on a ISOLUTE Silica Flash column (50 g)

ORD record

ord-98849274ff4f45369246dc040b47c912

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08415378B2