Phosphorus sulfide (P2S5) → HCID 86749225, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 1.12 g (3.16 mmol) of (3RS,5R)-2-oxo-3-ethylcarboxy-5-[2-(4-bromophenyl)ethyl]piperidine and 0.77 g (1.74 mmol) of phosphorus pentasulfide in 20 mL of tetrahydrofuran was heated at 60° C. until complete conversion was obtained (about 3 hours). The mixture was evaporated to a residue which was purified by chromatography on silica gel. The product was eluted with ethyl acetate-hexane 1:1, affording 0.729 g (61%) of (3RS,5R) -2-thioxo-3-ethylcarboxy-5-[2-(4-bromophenyl)ethyl]piperidine (mixture of C-3 epimers)), mp 105°-115° C., 1H NMR (300 MHz, CDCl3) δ 9.47 (s, 1H), 7.41 (d, J=8.7 Hz,); 7.39 (d, J=8.2 Hz,), total 2H, 7.02 (d, J=8.7 Hz, 2H), 4.20 (m, 2H), 3.94 (m); 3.69 (m), total 1H, 3.45 (m, 1H), 2.99 (m, 1H), 2.60 (m, 2H), 2.13 (m, 2H), 1.5-1.87 (m, 3H), 1.31 (t, J=7.1 Hz); 1.26 (t, J=7.1 Hz), total 3H; IR (CHCl3) 2983, 1731, 1540, 1489, 1373, 1073, 1012 cm-1 ; MS (FD) m/z 371 (100), 369 (75); UV (EtOH) 219.8 nm (ε 13 174), 281.4 (13 557); Anal. Calcd for C16H20BrNO2S: C, 51.90; H, 5.44; N, 3.78. Found: C, 51.61; H, 5.38; N, 3.88.

Provenance & Evidence