Triethylamine → Ethyl 1,4-dibenzylpiperazine-2-carboxylate

HRID 417824Notes

Reaction equation

[CH2:1]([NH:8][CH2:9][CH2:10][NH:11][CH2:12][C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(N(CC)CC)C.Br[CH:27]([CH2:33]Br)[C:28]([O:30][CH2:31][CH3:32])=[O:29]>C1(C)C=CC=CC=1>[CH2:1]([N:8]1[CH2:9][CH2:10][N:11]([CH2:12][C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)[CH2:33][CH:27]1[C:28]([O:30][CH2:31][CH3:32])=[O:29])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

Conditions

Temperature: 80 °C

Procedure

To a hot (about 80° C.) solution of N,N′-dibenzylethylenediamine (216 g, 0.9 mol) and triethylamine (300 uL, 2.16 mol) in toluene (650 mL) was added rapidly dropwise ethyl 2,3-dibromopropionate (240 g, 0.93 mol) in toluene (650 mL). After the addition, the reaction mixture was stirred at 80° C. for about three hours. A temperature below about 95° C. was maintained. The heavy precipitate was filtered off and then solvent and excess TEA removed. t-butyl methyl ether (about 300 mL) was added. The reaction was stirred well, and any precipitate that was formed was filtered. The reaction was concentrated to a pale yellow oil (about 287 g, about 94%)

Workup

additionAfter the addition
temperatureA temperature below about 95° C. was maintained
filtrationThe heavy precipitate was filtered off
customsolvent and excess TEA removed
additiont-butyl methyl ether (about 300 mL) was added
stirringThe reaction was stirred well
customany precipitate that was formed
filtrationwas filtered
concentrationThe reaction was concentrated to a pale yellow oil (about 287 g, about 94%)

Sources & evidence

ORD record: ord-cb300ce0a3de4c42833c5a16151d33bb
Source dataset: uspto-grants-2012_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08093237B2

Reaction notes

Loading…