4-[(dimethylamino)sulfonyl]-1-Piperazinecarboxylic acid 1,1-dimethylethyl ester synthesis

Yield:253176-45-3 100%

Reaction Conditions:

with N-ethyl-N,N-diisopropylamine in dichloromethane at 20; for 24 h;Inert atmosphere;

Steps:

General procedure for the synthesis of intermediates 4 and 5

General procedure: Under an inert atmosphere (N₂), amixture of Boc-piperazine1-1carboxylate (1eq), Dimethyl-sulfamoylchloride (1eq), and N-ethyl-N-isopropylpropan-2-amine (1eq) in DCMwas stirred at room temperature for 24h. The reaction mixture was diluted into100ml of water, and then extracted with DCM (10ml ×6). The organic layers werecombined then dried over Na₂SO₄ and concentrated invacuum to provide the wanted intermediate 4(yield of 100%) which was further reacted in DCM/TFA (7:3) at room temperature.After the reaction was completed, the solution was diluted in water, and then 1NKOH was used to make the solution slightly basic. The wanted compound 5 was obtained after extraction from the solution byDCM and drying under reduced pressure; to be used directly in the next stepwithout further purification

References:

Cherfaoui, Bahidja;Guo, Tian-Kun;Sun, Hao-Peng;Cheng, Wei-Lin;Liu, Fang;Jiang, Fen;Xu, Xiao-Li;You, Qi-Dong [Bioorganic and Medicinal Chemistry,2016,vol. 24,# 11,p. 2423 - 2432] Location in patent:supporting information