N-bromobutanimide → Methyl(2S)-2-[(22S)-8-bromo-17-fluoro-4,18,22,28-tetramethyl-21,27-dioxa-1,7,34-triazahexacyclo[26.2.2.16,9.110,14.02,7.015,20]tetratriaconta-2,4,6(34),8,10(33),11,13,15(20),16,18-decaen-3-yl]-2-(tert-butoxy)acetate

Participants

Reaction Steps

To a solution of methyl(2S)-2-(tert-butoxy)-2-[(22S)-17-fluoro-4,18,22,28-tetramethyl-21,27-dioxa-1,7,34-triazahexacyclo[26.2.2.16,9.110,14.02,7.015,20]tetratriaconta-2,4,6(34),8,10(33),11,13,15(20),16,18-decaen-3-yl]acetate (50 mg, 0.074 mmol, 1 equiv) in MeCN (1.5 mL) was added NBS (13 mg, 0.074 mmol, 1 equiv). After 1 h, the reaction was concentrated in vacuo. The crude product was purified by flash column chromatography (0-100% EtOAc [2% TEA]/hexane) to provide the product (40 mg, 72%). 1H NMR (400 MHz, CHLOROFORM-d) δ 8.16 (s, 1H), 7.82 (d, J=7.8 Hz, 1H), 7.54 (t, J=7.7 Hz, 1H), 7.37 (d, J=7.8 Hz, 1H), 7.29 (s, 1H), 6.97 (d, J=10.3 Hz, 1H), 6.85 (d, J=6.5 Hz, 1H), 4.58-4.37 (m, 2H), 3.82-3.66 (m, 4H), 3.64-3.55 (m, 1H), 3.46-3.38 (m, 1H), 2.47 (br. s., 3H), 2.30 (d, J=0.8 Hz, 4H), 1.98-1.69 (m, 8H), 1.66-1.48 (m, 4H), 1.31-1.26 (m, 7H), 1.24 (d, J=5.8 Hz, 8H), 1.15 (d, J=6.0 Hz, 3H).

Provenance & Evidence