Synthesis,Crystal Structure and Spectroscopic Properties of 1,2-Benzothiazine Derivatives:An Experimental and DFT Study  

作　　者：MUHAMMAD Nadeem Arshad TARIQ Mahmood ATHER Faroque Khan MUHAMMAD Zia-Ur-Rehman ABDULLAH M.Asiri ISLAM Ullah Khan RIFFAT-Un-Nisa KHURSHID Ayub AZAM Mukhtar MUHAMMAD Tariq Saeed 

机构地区：[1]Chemistry Department,Faculty of Science,King Abdulaziz University [2]Centre of Excellence for Advanced Materials Research (CEAMR),King Abdulaziz University [3]Department of Chemistry,COMSATS Institute of Information Technology,Abbottabad [4]IRCBM,COMSATS Institute of Information Technology [5]Applied Chemistry Research Center,PCSIR Laboratories Complex,Ferozpur Road,Lahore 54600,Pakistan [6]Materials Chemistry Laboratory,Department of Chemistry,GC University [7]Department of Chemistry,College of Science,King Faisal University [8]Department of Chemistry,University of Education,Okara Campus,Okara-Pakistan

出　　处：《Chinese Journal of Structural Chemistry》2015年第1期15-25,共11页结构化学（英文）

基　　金：funded by the Saudi Basic Industries Corporation(SABIC) and the Deanship of Scientific Research(DSR),King Abdulaziz University,Jeddah,under grant no.(MS/15/396/1434)

摘　　要：1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.

关 键 词：1 2-benzothiazine B3LYP/6-31＋G （d） density functional theory （DFT） HUMO-LUMO crystal structures 

分 类 号：O643.12[理学—物理化学]