Vol.:(0123456789) 1 3 J Chem Crystallogr DOI 10.1007/s10870-017-0697-8 ORIGINAL PAPER Crystal Structure, Spectroscopic and DFT Studies on E and Z Isomers of Ethyl 2-(2,3-dioxo-2,3-dihydro-1H-indol-1-yl)-3- phenyl-2-propenoate Ali Ramazani 1  · Masoome Sheikhi 2  · Hamideh Ahankar 3  · Morteza Rouhani 4  · Sang Woo Joo 5  · Katarzyna Ślepokura 6  · Tadeusz Lis 6   Received: 6 July 2015 / Accepted: 8 August 2017 © Springer Science+Business Media, LLC 2017 Graphical Abstract Keywords Crystal structures · DFT · DOS · NBO analysis Introduction Acrylic compounds have great reactivity as electrophiles towards nucleophiles, particularly in the preparation of natural and biologically active compounds [1, 2], therefore they are good Michael acceptors [3]. Acrylates are salts, esters, and conjugate bases of acrylic acid and its deriva- tives. They are also known as propenoates. Acrylates easily form polymers because the double bonds are very reactive. These polymers play an important role in military and com- mercial products [4]. Compounds containing alkyl acrylate skeletons have signifcant importance in material science [5]. Abstract The crystal structures of two compounds,ethyl- (E)-2-(2,3-dioxo-2,3-dihydro-1H-indol-1-yl)-3-phenyl-2- propenoate and ethyl-(Z)-2-(2,3-dioxo-2,3-dihydro-1H- indol-1-yl)-3-phenyl-2-propenoate were determined from single-crystal X-ray difraction and characterized by FT-IR, 1 HNMR and 13 CNMR spectroscopy. The quantum theoreti- cal calculations for two structures were performed by den- sity functional theory (DFT/B3LYP/6-311+G*). From the optimized structure, geometric parameters were obtained and experimental measurements were compared with the calculated data. Frontier molecular orbitals, total density of states, molecular electrostatic potential, molecular proper- ties, thermodynamic parameters and NBO analysis for E and Z isomers were investigated by theoretical calculations. Electronic supplementary material The online version of this article (doi:10.1007/s10870-017-0697-8) contains supplementary material, which is available to authorized users. * Ali Ramazani aliramazani@gmail.com * Sang Woo Joo 1 Department of Chemistry, University of Zanjan, P.O. Box 45195-313, Zanjan, Iran 2 Young Researchers and Elite Club, Gorgan Branch, Islamic Azad University, Gorgan, Iran 3 Department of Chemistry, Abhar Branch, Islamic Azad University, P O Box 22, Abhar, Iran 4 Young Researchers and Elite Club, Zanjan Branch, Islamic Azad University, Zanjan, Iran 5 School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749, Republic of Korea 6 Faculty of Chemistry, University of Wrocław, 14 Joliot-Curie St., 50-383 Wrocław, Poland