Reaktion #78262

Reaktionsgleichung

1-bromo-4-(2-bromoethyl)benzene

2-(3,5-dichlorophenyl)-tetrahydro-imidazo[1,5-a]pyrazine-1,3-dione

potassium carbonate

sodium iodide

→

7-[2-(4-bromophenyl)ethyl]-2-(3,5-dichlorophenyl)-tetrahydro-imidazo[1,5-a]pyrazine-1,3-dione

Lösungsmittel

methyl isopropyl ketone

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared
2. 2
   Einengenthe filtrate was concentrated under vacuum
3. 3
   Sonstigechromatographed over silica gel (CH2Cl2)
4. 4
   workup.ADDITIONThe obtained oil was treated with Et2O/HCl

Vorschrift

A mixture of 1-bromo-4-(2-bromoethyl)benzene (101 mg, 0.38 mmol, prepared as described in Synth.Commun [1996], 26, pp. 1467-1472), 2-(3,5-dichlorophenyl)-tetrahydro-imidazo[1,5-a]pyrazine-1,3-dione (100 mg, 0.33 mmol, Prep. 19), potassium carbonate (48 mg, 0.35 mmol) and sodium iodide (10 mg, 0.06 mmol) in methyl isopropyl ketone (2 mL) was heated at 100° C. for 48 h. The precipitate was discarded and the filtrate was concentrated under vacuum and chromatographed over silica gel (CH2Cl2). The obtained oil was treated with Et2O/HCl to yield the hydrochloride of 7-[2-(4-bromophenyl)ethyl]-2-(3,5-dichlorophenyl)-tetrahydro-imidazo[1,5-a]pyrazine-1,3-dione as a white solid (60 mg). 1H NMR (CDCl3) of the free base: 7.25-7.4 (5H, m), 7.00 (2H, d, J=8.3Hz), 4-4.15 (2H, m), 3.32 (1H, dd, J1=4.1 Hz, J2=11.1 Hz), 3.09 (1H, dt), 2.87 (1H, br d), 2.5-2.8 (4H, m), 1.95-2.15 (2H, m)

Quelle