Methyl iodide → tert-Butyl 3-cyano-3-methylazetidine-1-carboxylate

Temperature

-78 °C

To an oven-dried 25 mL round bottom flask equipped for stirring was added diisopropylamine (1.318 mL, 9.33 mmol) under nitrogen. THF (10 mL) was added and the colorless solution was cooled to 0° C. n-BuLi in hexanes (1.6N, 5.83 mL, 9.33 mmol) was added dropwise and the solution was stirred at 0° C. for 30 min. The solution was cooled to −78° C. and a solution of tert-butyl 3-cyanoazetidine-1-carboxylate (1 g, 5.49 mmol) in THF (3 mL) was added and the solution was stirred at −78° C. for 30 min. Iodomethane (0.445 mL, 7.13 mmol) was added dropwise at −78° C. The reaction mixture was stirred for 30 min; it was then allowed to slowly warm up to 25° C. and was stirred for 16 h. The reaction mixture was quenched at 0° C. with aqueous ammonium chloride (5 mL) and was extracted with DCM (3 times). The extracts were dried over Na2SO4. Purification by silica column chromatography (MeOH/DCM, 0-5%) afforded the title compound as a yellow oil (0.35 g, 32%). 1H NMR (500 MHz, CDCl3) δ 1.45 (s, 9 H) 1.67 (s, 3 H) 3.80 (d, J=8.30 Hz, 2 H) 4.29 (d, J=8.79 Hz, 2 H).

1. customTo an oven-dried 25 mL round bottom flask equipped
2. additionwas added dropwise
3. stirringthe solution was stirred at 0° C. for 30 min
4. stirringthe solution was stirred at −78° C. for 30 min
5. stirringThe reaction mixture was stirred for 30 min
6. temperatureto slowly warm up to 25° C.
7. stirringwas stirred for 16 h
8. customThe reaction mixture was quenched at 0° C. with aqueous ammonium chloride (5 mL)
9. extractionwas extracted with DCM (3 times)
10. dry with materialThe extracts were dried over Na2SO4
11. customPurification by silica column chromatography (MeOH/DCM, 0-5%)

ORD record

ord-93dffd2805ca47128db866a1d9c74f30

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08420816B2