4-BROMO-3-FORMYLINDOLE-1-CARBOXYLIC ACID TERT-BUTYL ESTER

General procedure: Boc20 ( 1.5 equiv.) followed by DMAP (0.3 equiv.) was added to a 46 mM solution of intermediate 2 ( 1 equiv.) in anhydrous THF. The reaction mixture was stirred at room temperature under nitrogen atmosphere. When no starting material was detected by TLC, H20 was added to the reaction mixture and the volatiles were evaporated under vacuo. The residual water phase was extracted with EtOAc. The pooled organic phase was washed with brine, dried over Na2S04, filtered and concentrated under vacuo to yield the intermediate 3. tert-Butyi 4-fluoro-3-formyl-lH-indole-l-carboxylate (intermediate 3a) Synthesis was carried out using the general procedure, using a 46 mM solution of intermediate 2a (1.76 g, 10.8 mmol), Boc20 (3.5 g, 16.2 mmol) and DMAP (0.4 g 3.2 mmol) in anhydrous THF to yield the title compound as white powder (2.77 g, 99% yield); m.p. 98- 100 C; Rf = 0.5 (hexane/EtOAc 2: 1); -NMR (400 MHz, CDC13): delta = 1.69 (s, 9H, Boc), 7.07 (m, 1Hz, 1H, H-7), 7.34 (dt, J = 8, 5 Hz, 1H, H-6), 8.02 (d, J = 8 Hz, 1H, H-5), 8.28 (s, 1H, H-2), 10.30 (d, J = 2 Hz, 1H, CHO) ppm; 1 C-NMR (100 MHz, CDC13) : delta = 28.4, 86.4, 1 10.3 (d, J = 20 Hz), 1 12. 1 (d, J = 3.6 Hz), 1 16.0 (d, J = 23 Hz), 120. 1 (d, J = 5.6 Hz), 126.7 (d, J = 7.3 Hz), 132. 1, 138.3 (d, J = 8.6 Hz), 148.9, 156.8 (d, J = 250 Hz), 186.2 (d, J = 3.6 Hz) ppm.

Molecular Weight:324.17
XLogP3:3.4
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:3
Exact Mass:323.01571
Monoisotopic Mass:323.01571
Topological Polar Surface Area:48.3
Heavy Atom Count:19
Complexity:366
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes