Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 80503Generated: October 28, 2026

Ethyl Bromide → 3-Ethyl-1,2,3,4,4a,5-hexahydropyrazino[1,2-a][1,5]benzodiazepin-6(7h)-one

https://huagongshe.com/reaction/80503

Reaction equation

Participants

RoleNameHCIDCharge
ReactantEthyl BromideHCID 6332—
ReactantPotassium CarbonateHCID 11430—
Reactant1,2,3,4,4a,5-Hexahydropyrazino[1,2-a][1,5]benzodiazepin-6(7h)-oneHCID 49764166—
SolventDimethylformamideHCID 6228—
Product3-Ethyl-1,2,3,4,4a,5-hexahydropyrazino[1,2-a][1,5]benzodiazepin-6(7h)-oneHCID 49764416—

Reaction Conditions

Temperature60 °C

Reaction Steps

To a solution of Example 1D (30 mg, 0.14 mmol) in N,N-dimethylformamide (1 mL) was added potassium carbonate (57 mg, 0.41 mmol) and bromoethane (10.3 μl, 0.14 mmol). The reaction was warmed to 60° C. for 14 hours. Excess potassium carbonate was filtered off. The solution was passed through a PS-isocyanate cartridge (Silicycle, 2 g) to trap leftover starting material. The solution was concentrated and purified by preparative HPLC with a gradient of acetonitrile and 0.1% trifluoroacetic acid in water to afford the title compound. 1H NMR (500 MHz, DMSO-d6/D2O) δ ppm 7.19-7.24 (m, 1H), 7.14-7.18 (m, 1H), 7.09-7.13 (m, 1H), 7.01 (dd, J=7.78, 1.37 Hz, 1H), 3.52-3.64 (m, 3H), 3.32-3.39 (m, 2H), 3.19-3.27 (m, 2H), 2.97-3.10 (m, 2H), 2.66 (dd, J=13.73, 7.02 Hz, 1H), 2.09 (d, J=13.12 Hz, 1H), 1.27 (t, J=7.32 Hz, 3H); MS (ESI) m/z 246.0 (M+H)+.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS08846663B2
Source datasetuspto-grants-2014_09
ORD IDord-598a8f7e574c42f194de753ea6b2c250
Source noteuspto-grants-2014_09