Tri-o-tolylphosphine → Tert-butyl 3-(3-(cyclopropylethynyl)phenyl)propylcarbamate

Temperature

90 °C

To a degassed solution of tert-butyl 3-(3-bromophenyl)propylcarbamate (57) (1.0 g, 3.1 mmol) and cyclopropyl acetylene (2.9 mL, 3.4 mmol, 70% soln in toluene) in diisopropylamine (4 mL) was added PdCl2(PPh3)2 (0.120 g, 0.17 mmol), tri-o-tolylphosphine (0.048 g, 0.16 mmol) and CuI (0.026 g, 0.16 mmol). The resulting mixture was degassed and stirred under nitrogen at 90° C. for overnight. The mixture was cooled to room temperature and concentrated under reduced pressure. The residue was partitioned between water and ethyl acetate. The organic layer was dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure. Purification by flash chromatography (10-40% ethyl acetate-hexane gradient) gave tert-butyl 3-(3-(cyclopropylethynyl)phenyl)propylcarbamate. Yield (0.756 g, 79%). This alkyne was used for deprotection without futher purification.

1. customThe resulting mixture was degassed
2. temperatureThe mixture was cooled to room temperature
3. concentrationconcentrated under reduced pressure
4. customThe residue was partitioned between water and ethyl acetate
5. dry with materialThe organic layer was dried over anhydrous Na2SO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customPurification by flash chromatography (10-40% ethyl acetate-hexane gradient)

ORD record

ord-748b5e92a8b247ab965c608f12f6c5ae

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08076516B2