O-Xylene → 2-Chloro-4,5-difluorobenzonitrile

HRID 129244

Reaction equation

[F-:1].[K+].CC(CC(O)CO)C.[Cl:11][C:12]1[CH:19]=[C:18](Cl)[C:17]([F:21])=[CH:16][C:13]=1[C:14]#[N:15].C1(C)C(C)=CC=CC=1>[Br-].C([P+](CCCC)(CCCC)CCCC)CCC>[Cl:11][C:12]1[CH:19]=[C:18]([F:1])[C:17]([F:21])=[CH:16][C:13]=1[C:14]#[N:15]

Participants

Conditions

Temperature: 130 °C

Procedure

In a 100 ml flange flask fitted with a distillation bridge and anchor stirrer, 14.5 g (0.25 mol) of potassium fluoride, 4.8 g (0.007 mol) of trimethyl(ethoxypolyoxypropyl)ammonium chloride, 6.2 g (0.012 mol) of polyethylene glycol dimethyl ether 500 and 2.4 g (0.007 mol) of tetrabutylphosphonium bromide were introduced at 100° C. into the melt of 47.5 g (0.25 mol) of 2,4-dichloro-5-fluorobenzonitrile. Subsequently, 10 g (0.09 mol) of xylene were added and the reaction suspension was azeotropically dried by application of a vacuum of 20 mbar and heating to 130° C. After the xylene had been distilled off, the reaction suspension was heated to 140° C. and stirred for 8 hours at this temperature. Amount of 2-chloro-4,5-difluorobenzonitrile formed:

Workup

customthe reaction suspension was azeotropically dried by application of a vacuum of 20 mbar
distillationAfter the xylene had been distilled off
temperaturethe reaction suspension was heated to 140° C.

Sources & evidence

ORD record: ord-6f0eb02cbc95451ca753776a47119975
Source dataset: uspto-grants-1995_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05466859

Linked notes

Loading…