Hexane → HCID 60077543, compound

Solution of BuLi (2.5M) in hexane (9.6 ml; 0.024 mol) was added to a stirred solution of 2,5-difluoroanisol (2.88 g, 0.02 mol) in dry THF (30 ml) at −70 C, followed after 2 h by solution of zinc chloride (3.6 g; 0.026 mol) in dry THF (50 ml). The reaction temperature was allowed to raise to room temperature and then stirring was maintained at room temperature for 30 min. Pd(OAc)2 (8 mg; 0.2 mol %) was added, followed by ethyl cis-3-bromoacrylate (3.58 g; 0.02 mol). The reaction mixture was placed in preheated oil bath and heated under reflux for 1 h. The resulting reaction mixture was chilled to −78 C and 60 ml (0.06 mol) of DIBAL (1M solution in hexanes) was added dropwise. The stirring was continued at −78 C for 2 h and 1 h at room temperature. The reaction was quenched with water and all solids were dissolved by addition of HCl. The organic phase was diluted with ether, separated, washed with 5N HCl, brine and evaporated in vacuo. The residue was Kugelrohr distilled (1.5×10−2 mbar, 150 C) to give 3.7 g (92%) of crude (2Z)-3-(3,6-difluoro-2-methoxyphenyl)-2-propen-1-ol, which contains ˜6% of other regioisomers. The crude product was used in the next step without further purification.

1. temperaturewas maintained at room temperature for 30 min
2. customThe reaction mixture was placed in preheated oil bath
3. temperatureheated
4. temperatureunder reflux for 1 h
5. customThe resulting reaction mixture
6. additionwas added dropwise
7. customThe reaction was quenched with water
8. dissolutionall solids were dissolved by addition of HCl
9. additionThe organic phase was diluted with ether
10. customseparated
11. washwashed with 5N HCl, brine
12. customevaporated in vacuo
13. distillationdistilled (1.5×10−2 mbar, 150 C)

ORD record

ord-9afbe0e72e574d908fad42f376717b7f

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07517992B2