N1,N1,N2,N2-Tetramethylethylenediaminium-N1,N2-disulfonic Acid Trifluoroacetate as Highly Effectual and Dual-Functional Catalyst for the Reaction of β-Ketoesters with Aryl Aldehydes and Urea/Thiourea Journal title: Chemical Methodologies Authors: Mostafa Karami, Bentolhoda Gholami, Tahereh Hekmat Zadeh, Abdolkarim Zare Subject(s):