Ethyl indole-2-carboxylate → Ethyl 7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole-2-carboxylate

HRID 576271Notes

Reaction equation

HRID 576271 reaction equation
[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH:3]=[C:2]1[C:10]([O:12][CH2:13][CH3:14])=[O:11].C(C1C=CC(C2C=CC(C(C)(C)C)=CN=2)=NC=1)(C)(C)C.[CH3:35][C:36]1([CH3:43])[C:40]([CH3:42])([CH3:41])[O:39][BH:38][O:37]1>>[CH2:13]([O:12][C:10]([C:2]1[NH:1][C:9]2[C:4]([CH:3]=1)=[CH:5][CH:6]=[CH:7][C:8]=2[B:38]1[O:39][C:40]([CH3:42])([CH3:41])[C:36]([CH3:43])([CH3:35])[O:37]1)=[O:11])[CH3:14]

Participants

4

Reactant 3

HCID 73125Ethyl indole-2-carboxylateHCID 27347684,4,5,5-Tetramethyl[1,3,2]dioxaborolaneHCID 12010937HCID 12010937, compound

Product 1

HCID 16050160Ethyl 7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole-2-carboxylate

Conditions

Temperature
62 °C

Procedure

A mixture of ethyl 1H-indole-2-carboxylate (1.89 g), 5,5′-di-tert-butyl-2,2′-bipyridine (0.081 g), and (Ir(OMe)(COD))2 (0.152 g) in hexanes (30 mL) was treated with 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.66 g) via a syringe. The reaction mixture was degassed via vacuum/nitrogen cycle three times. The reaction mixture was heated at 62° C. for 12 hours. After this time, the solvent was removed and the residue was purified by flash chromatography on silica gel eluting with 1:9 ethyl acetate/hexane to give the title compound. 1H NMR (500 MHz, DMSO-d6): 9.75 (s, 1H), 7.87 (d, J=7.93 Hz, 1H), 7.64-7.65 (m, 1H), 7.24 (s, 1H), 7.16-7.17 (m, 1H), 4.36 (q, J=7.02 Hz, 2H), 1.38 (s, 12H), 1.35 (q, J=7.02 Hz, 3H).

Workup

  1. customThe reaction mixture was degassed via vacuum/nitrogen cycle three times
  2. customAfter this time, the solvent was removed
  3. customthe residue was purified by flash chromatography on silica gel eluting with 1:9 ethyl acetate/hexane

Sources & evidence

ORD record
ord-3d284ea9ecbd40f89e656bbeb13e333f
Source dataset
uspto-grants-2015_05
Patent number
US09035047B2

Reaction notes

Loading…