Tributyltin Chloride → tert-butyl N-(5-(tributylstannyl)-1,3-thiazol-2-yl)carbamate

温度

-78 °C

A solution of tert-butyl thiazol-2-ylcarbamate (15.0 g, 75 mmol), in THF (200 mL) was stirred at −78° C. and then n-butyl lithium (63 mL, 157 mmol) was added dropwise over 15 minutes. The resulting solution was stirred at −78° C. for 30 minutes, and then tributyltin chloride (22 mL, 82 mmol) was then added dropwise. The resulting pale yellow mixture was stirred for 30 minutes at −78° C. The bath was then removed, and the mixture was allowed to warm to room temperature. The reaction was then stirred for 2.5 hours. The reaction mixture was quenched with a saturated NH4Cl solution (300 mL). The layers were separated, and the aqueous layer was extracted with ether (3×100 mL). The organic layers were combined, washed with brine (300 mL), dried over MgSO4, filtered, and concentrated. The crude product was adsorbed onto a plug of silica gel and chromatographed through a Redi-Sep pre-packed silica gel column (330 g), eluting with a gradient of 10% to 20% EtOAc in hexanes, to provide the title compound (30 g, 81%) LCMS (M+H+) 490.1 calc. for C20H38N2O2SSn 490.1; 1H NMR (400 MHz, CDCl3) δ ppm 7.31 (s, 1H), 1.59 (s, 9H), 1.30 (tt, 6H), 1.54 (t, 6H), 1.10 (qt, 6H), 0.80 (t, 9H).

1. stirringThe resulting pale yellow mixture was stirred for 30 minutes at −78° C
2. customThe bath was then removed
3. temperatureto warm to room temperature
4. stirringThe reaction was then stirred for 2.5 hours
5. customThe reaction mixture was quenched with a saturated NH4Cl solution (300 mL)
6. customThe layers were separated
7. extractionthe aqueous layer was extracted with ether (3×100 mL)
8. washwashed with brine (300 mL)
9. dry with materialdried over MgSO4
10. filtrationfiltered
11. concentrationconcentrated
12. customchromatographed through a Redi-Sep pre-packed silica gel column (330 g)
13. washeluting with a gradient of 10% to 20% EtOAc in hexanes

ORDレコード

ord-7fb2a574f173497fa98863266f68e1ea

出典データセット

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08084479B2