Reaction #10509

Reaction equation

5-bromo-1-methyl-2-[2-(2-methyl-pyrrolidin-1-yl)-ethyl]-1H-indole

5-bromo-1-methyl-2-[2-(2-methyl-pyrrolidin-1-yl)-ethyl]-1H-indole

Cs2CO3

CsF

4-cyanophenylboronic acid

→

title compound

Yield 44.8%

4-{1-Methyl-2-[2-(2-(R)-methyl-pyrrolidin-1-yl)-ethyl]-1H-indol-5-yl}-benzonitrile

Yield 44.8%

Solvents

toluene

H2O

Conditions

Workup

1. 1
   OtherThe resulting mixture was purged with nitrogen
2. 2
   OtherThe resulting reaction mixture
3. 3
   Otherwas consumed
4. 4
   TemperatureThe reaction mixture was cooled to room temperature
5. 5
   workup.ADDITIONIPAc (20 mL) was added
6. 6
   OtherThe organic layer was separated
7. 7
   Concentrationconcentrated
8. 8
   OtherThe residue was purified by column chromatograph
9. 9
   Washeluting with heptane/acetone/CH2Cl2/Et3N (600 mL/40/mL/5 mL/2 mL)
10. 10
    workup.ADDITIONThe fractions containing product
11. 11
    Concentrationconcentrated under reduced pressure

Procedure

A reaction flask was charged with Cs2CO3 (1.14 g, 3.5 mmol), CsF (0.38 g, 2.5 mmol), 4-cyanophenylboronic acid (425 mg, 2.5 mmol), and H2O (10 mL) followed by a toluene solution (10 mL) of 5-bromo-1-methyl-2-[2-(2-methyl-pyrrolidin-1-yl)-ethyl]-1H-indole (320 mg, 1.0 mmol). The resulting mixture was purged with nitrogen. To the reaction mixture was then added Cy2PPh2(5-bromo-2-[2-(R)-methyl-pyrrolidin-1-yl)-ethyl]-1H-indole) (35 mg, 0.1 mmol) and Pd2(dba)3 (46 mg, 0.05 mmol). The resulting reaction mixture was then heated to 65° C. overnight under nitrogen. HPLC indicated that all of the 5-bromo-1-methyl-2-[2-(2-methyl-pyrrolidin-1-yl)-ethyl]-1H-indole was consumed. The reaction mixture was cooled to room temperature and IPAc (20 mL) was added. The organic layer was separated and concentrated. The residue was purified by column chromatograph eluting with heptane/acetone/CH2Cl2/Et3N (600 mL/40/mL/5 mL/2 mL). The fractions containing product were combined and concentrated under reduced pressure to provide the title compound as a semisolid (154 mg). 1H NMR (400 MHz, CDCl3) δ 7.57–7.66 (m, 5H), 7.30 (dd, J=1.7, 8.6Hz, 1H), 7.25 (d, J=8.51 Hz, 1H), 6.27 (S, 1H), 3.63 (S, 1H), 3.21–3.25 (m, 1H), 3.06–3.13 (m, 1H), 2.87–2.93 (m, 2H), 2.33–2.40 (m, 2H), 2.16 (q, J=8.78 Hz, 1H), 1.84–1.91 (m, 1H), 1.65–1.76 (m, 2H), 1.36–1.44 (m, 1H), 1.07 (d, J=6.1 Hz, 3H). 13C NMR (400 MHz, CDCl3) δ 146.80, 140.39, 137.11, 132.04, 130.19, 128.11, 127.27, 119.86, 119.08, 118.43, 109.18, 99.37, 60.15, 54.19, 53.24, 32.89, 29.91, 26.85, 21.98, 19.32. [M+H]+ at m/z 344.

Source