Pyridine → Tert-butyl 4-[4-(chloromethyl)-1,3-thiazol-2-yl]piperidine-1-carboxylate

Beteiligte Stoffe

Reaktionsschritte

1,1-Dimethylethyl 4-(aminocarbonothioyl)piperidine-1-carboxylate (1.50 g, 6.14 mmol), NaHCO3 (0.570 g, 6.78 mmol) and 1,3-dichloroacetone (0.860 g, 6.77 mmol) were combined in 1,2-dichloroethane (4 mL) and the reaction mixture was stirred at room temperature for 12 h. The crude reaction mixture was filtered using CH2Cl2 and the filtrate was concentrated in vacuo until approximately 30 mL of solvent remained. To this solution was added pyridine (0.75 mL, 9.2 mmol), and the solution was cooled with an ice bath. Thionyl chloride (0.49 mL, 6.8 mmol) was added and the solution was allowed to warm slowly to room temperature. The solvent was removed in vacuo and the residue was taken up in 10% MeOH/ethyl acetate (100 mL). The organic layer was washed with H2O (100 mL) and brine (100 mL), dried (Na2SO4), filtered, and concentrated in vacuo to yield 2.24 g (>100%) of crude 1,1-dimethylethyl 4-[4-(chloromethyl)-1,3-thiazol-2-yl]piperidine-1-carboxylate as a colorless oil. 1H NMR (400 MHz, d6-DMSO): 7.62 (s, 1H), 4.60 (s, 2H), 3.98 (m, 1H), 3.63 (dd, 2H), 3.16 (m, 1H), 2.90 (broad s, 2H), 2.01 (dd, 1H), 1.51 (m, 2H), 1.40 (s, 9H). MS (EI) for C14H21N2O2SCl: 261 (M−tBu).

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