Lawesson's reagent → 4-bromo-3-chloro-N-trimethylsilanylmethylthiobenzamide

Participants

Reaction Steps

To a solution of 4-bromo-3-chloro-N-trimethylsilanylmethyl-benzamide (Example I12) (4.6 g) in toluene (150 ml) was added 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (Lawesson reagent) (5.8 g). The reaction mixture was stirred at ambient temperature for 30 minutes and then at 110° C. for 1.5 hours. The reaction mixture was concentrated and the residue purified by chromatography on silica gel (eluent: ethyl acetate/heptanes 1:5) to give 4-bromo-3-chloro-N-trimethylsilanylmethylthiobenzamide (4.64 g). 1H-NMR (400 MHz, CDCl3): 1H-NMR (400 MHz, CDCl3): 7.60 (d, 1H), 7.45 (s, 1H), 7.30 (s, 1H), 7.25 (d, 1H), 3.33 (d, 2H), 0.00 (s, 9H) ppm.

Provenance & Evidence