Trimethylsilyl triflate → HCID 67960564, compound

Participants

Reaction Steps

A solution of (S)-1-{(S)-2-((S)-2-tert-butoxycarbonylamino-3-methyl-butyrylamino)-3-[3-(tert-butyl-dimethyl-silanyloxy)-phenyl]-propionyl}-hexahydro-pyridazine-3-carboxylic acid 3-vinyl-benzyl ester (300 mg, 0.42 mmol) in anhydrous dichloromethane (9 mL) was treated with trimethylsilyl trifluoromethanesulfonate (114 μL, 0.63 mmol). The reaction mixture was stirred at room temperature for 1.5 hours then N,N-diisopropylethylamine (293 μL, 1.68 mmol) was added. The reaction mixture was evaporated to give the crude amine as a colourless solid. A solution of (2R,3R)-3-ethoxy-2-methyl-hept-6-enoic acid (78 mg, 0.42 mmol) in anhydrous dichloromethane (8 mL) was cooled to 0° C. before adding N,N-diisopropylethylamine (2934, 1.68 mmol) and 2-(7-aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (160 mg, 0.42 mmol). The mixture was stirred at 0° C. for 20 minutes before adding a solution of the crude amine in dichloromethane (8 mL). The reaction mixture was allowed to warm to room temperature and was stirred under a nitrogen atmosphere for 16 hours. The reaction mixture was evaporated and purified by silica gel chromatography using iso-hexanes/ethyl acetate 1:1 to yield the title compound (200 mg, 60%) as a colourless solid. 1H NMR (300 MHz, CDCl3) δ0.17 (s, 6H), 0.88-0.99 (m, 6H), 0.97 (s, 9H), 1.08-1.30 (m, 8H), 1.34-1.60 (m, 3H), 1.61-1.87 (m, 4H), 2.09-2.26 (m, 3H), 2.38-2.55 (m, 2H), 3.39-3.72 (m, 4H), 4.24-4.36 (m, 2H), 4.91-5.19 (m, 4H), 5.30 (d, J=10.9 Hz, 1H), 5.70-5.90 (m, 3H), 6.53-6.84 (m, 6H), 6.97-7.50 (m, 1H), 7.21-7.44 (m, 4H). LCMS (m/z) 791.4 [M+H] Tr=6.01 min.

Provenance & Evidence