1,2-Dimethoxyethane → 5-(1H-indol-5-yl)-pyrazin-2-ylamine

HRID 719996Notes

Reaction equation

[NH:1]1[C:9]2[C:4](=[CH:5][C:6](B(O)O)=[CH:7][CH:8]=2)[CH:3]=[CH:2]1.[NH2:13][C:14]1[CH:19]=[N:18][C:17](Br)=[CH:16][N:15]=1.C(=O)([O-])[O-].[Na+].[Na+].C(COC)OC>Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.O>[NH:1]1[C:9]2[C:4](=[CH:5][C:6]([C:17]3[N:18]=[CH:19][C:14]([NH2:13])=[N:15][CH:16]=3)=[CH:7][CH:8]=2)[CH:3]=[CH:2]1

Participants

Conditions

Temperature: 90 °C

Procedure

Nitrogen was bubbled through a solution of 5-indolylboronic acid (340 mg, 2.11 mmol), 2-amino-5-bromopyrazine (245 mg, 1.41 mmol), sodium carbonate (493 mg, 4.65 mmol), dimethoxyethane (12 mL), and water (4 mL) for 15 min. After this time, the solution was treated with dichlorobis(triphenylphosphine)palladium(II) (98 mg, 0.14 mmol), and the resulting reaction mixture was heated at 90° C. for 2 d. The reaction was then poured into water (50 mL) and extracted with ethyl acetate (3×50 mL). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 35/65 hexanes/ethyl acetate) afforded 5-(1H-indol-5-yl)-pyrazin-2-ylamine (122 mg, 41%) as a brown solid: EI-HRMS m/e calcd for C2H10N4 (M+) 210.0905, found 210.0901.

Workup

customthe resulting reaction mixture
extractionextracted with ethyl acetate (3×50 mL)
dry with materialThe combined organic layers were dried over magnesium sulfate
filtrationfiltered
concentrationconcentrated in vacuo

Sources & evidence

ORD record: ord-d5a267116bb14060ac43d0c83651afc1
Source dataset: uspto-grants-2006_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07132425B2

Reaction notes

Loading…