1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 z Inorganic Chemistry Naphthalene Based Amide-Imine Derivative and its Dinuclear Vanadium Complex: Structures, Atmospheric CO 2 Fixation and Theoretical Support Sabyasachi Ta, [a] Milan Ghosh, [a] Rostam Ali Molla, [a, d] Subhasis Ghosh, [a] Manirul Islam,* [b] Paula Brandão, [c] Vítor Félix,* [c] and Debasis Das* [a] The oxo-vanadium(V) complex (1) derived from an amide-imine conjugate, (E)-N’-(4-(diethylamino)-2-hydroxybenzylidene)-2- (naphthalen-1-yl)acetohydrazide (H 2 L 1 ) is exploited as catalyst for arresting atmospheric CO 2 to organic cyclic carbonate by reacting with epoxide. The H 2 L 1 is prepared by facile condensa- tion of 2-(naphthalen-1-yl)acetohydrazide (AC) and 4-(diethyla- mino)-2-hydroxybenzaldehyde in good yield. The 1 is charac- terized by single crystal X-ray diffraction, FTIR and absorption spectroscopic studies. Introduction The use of carbon dioxide, an abundant, inexpensive and nontoxic source of chemical carbon in organic synthesis has drawn much attention to academic and industrial scientists for last two decades. [1 10] Being a greenhouse gas, utilization of atmospheric CO 2 to synthesis organic compounds is challeng- ing and essential for sustainable development. [11,12] The major obstacle to activate and convert CO 2 into useful chemicals is its thermodynamic and kinetic stablity. [13,14] In this context, the reaction of epoxide with CO 2 leading to five-member cyclic carbonate is strategically useful. [15–17] More- over, cyclic carbonates are widely used as electrolyte in lithium- ion battery, aprotic solvent, as intermediate during production of pharmaceuticals and fine chemicals. [18–19] Till date, significant number of homogeneous [20] and heterogeneous catalysts, [21] mostly are Schiff bases or their metal complexes with Cr(III), Co (III), Al(III), Sn(II/IV), Cu(II), and Zn(II) have been used for preparation of five-membered cyclic carbonates. [22–25] Besides, ammonium salts, [26] ionic liquids, [27] N-heterocyclic compounds, [28] functional polymers, [29] and metal organic frameworks [30–32] have also been used for this purpose. How- ever, in most cases, satisfactory yield of cyclic carbonate requires high pressures (> 5 atm), additives, co-catalyst and organic solvent. Amide functionality [33] is widely encountered in biological and pharmaceutical [34] research for its strategic relation with protein and drug molecule. Interestingly, ∼ 25% of existing drug molecules bears amide functionality. [35] Stability, high polarity and conformational diversity of amide functionality is key factors for its use in organic and medicinal chemistry. [36] The non-toxic [37] vanadium mediated oxidation of organic substrates like olefin, thioether, amine and phosphine using various oxidizing agents have been reported. [38,39] The Lewis acidity of high oxidation state vanadium complexes is respon- sible for efficient epoxide activation/ ring opening in presence of appropriate nucleophile. In this context, arresting of atmospheric CO 2 in the form of cyclic carbonate is noteworthy and current topic of interest. Thus, Lee and co-workers studied the catalytic reaction between terminal epoxide/ cyclohexene oxide and carbon dioxide at elevated temperature (90–120○C) and pressure (14.8 bar).using commercial vanadium trichloride as catalyst. [40] Chatelet et al. reported metal-free organo-catalyst for synthesis of five-membered cyclic carbonate at atmospheric pressure and temperature. [41] Inspired by these facts, an amide-imine conjugate (H 2 L 1 , Scheme 1) is prepared by reacting 2-(naphthalen-1-yl)acetohy- drazide (AC) with 4-(diethylamino)-2-hydroxybenzaldehyde. The reaction of H 2 L 1 with VOSO 4 leads to methoxy bridged dinuclear dioxo-vanadium complex viz. [VO(L 1 )(μ-OMe)] 2 (1) (Scheme 2). Both H 2 L 2 and 1 are structurally characterized by single crystal X-ray diffraction analysis. The 1 is used for fixation of atmospheric CO 2 into cyclic carbonate through reaction with epoxide. Attempts have been made to provide theoretical support of the proposed CO 2 fixation mechanism. [a] S. Ta, M. Ghosh, Dr. R. A. Molla, S. Ghosh, Prof. D. Das Department of Chemistry, The University of Burdwan, Burdwan, 713104, W.B., India E-mail: ddas100in@yahoo.com [b] Prof. M. Islam Department of Chemistry, University of Kalyani, Kalyani, Nadia, 741235, India E-mail: manir65@rediffmail.com [c] Dr. P. Brandão, Prof. V. Félix Department of Chemistry, CICECO – Aveiro Institute of Materials, University of Aveiro, 3810-193, Aveiro, Portugal E-mail: vitor.felix@ua.pt [d] Dr. R. A. Molla Department of Science and Humanities, S. N. Bose Govt. Polytechnic College, Ratua, Malda, 73213, India Supporting information for this article is available on the WWW under https://doi.org/10.1002/slct.201901327 Full Papers DOI: 10.1002/slct.201901327 10254 ChemistrySelect 2019, 4, 10254–10259 © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim