Tetramethyltin → 5-Chloro-6-methyl-1,3-dihydro-isoindole-2-carboxylic acid tert-butyl ester

Temperature

50 °C

Lit. Tetrahedron Lett. 1999, 40, 2719-2722. To a stirred suspension of 1.58 mmol 5-chloro-6-iodo-1,3-dihydro-isoindole-2-carboxylic acid tert-butyl ester (Example A3(c)) in 3 ml N-methylpyrolidone were added 0.05 mmol tris(dibenzylideneacetone)dipalladium chloroform complex and 0.32 mmol triphenylphosphine and the mixture was stirred at 50° C. for 10 min. 0.16 mmol copper(I) iodide was then added and the mixture stirred at 50° C. for a further 10 min. Finally, 3.48 mmol tetramethyl tin was added and the reaction mixture was stirred at 80° C. for 16 h. The mixture was then cooled to room temperature, diluted with ethyl acetate and washed twice with brine. The organic phase was dried over sodium sulfate and concentrated in vacuo. The residue was purified by chromatography (SiO2, heptane/ethyl acetate) to yield the title compound as a yellow solid. MS (m/e): 214.1 ({37Cl}[M+H-Me2C═CH2]+, 35%), 212.0 ({35Cl}[M+H-Me2C═CH2]+, 100%).

1. stirringthe mixture stirred at 50° C. for a further 10 min
2. stirringthe reaction mixture was stirred at 80° C. for 16 h
3. temperatureThe mixture was then cooled to room temperature
4. washwashed twice with brine
5. dry with materialThe organic phase was dried over sodium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue was purified by chromatography (SiO2, heptane/ethyl acetate)

ORD record

ord-1ba9b91d41b543c7805dbcd7cc9df656

Source dataset

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08188139B2