Frared spectroscopy (FTIR) spectra had been recorded on a Shimadzu FTIR 4200 spectrophotometer (Shimadzu, Tokyo, Japan). The melting points had been recorded on a Gallenkamp apparatus (Calgary, AB, Canada). The element contents were determined working with a Vario EL III elemental analyzer (Elementar Americas, Ronkonkoma, NY, USA). The 1 H (500 MHz) and 119 Sn nuclear magnetic resonance (NMR, 149 MHz) spectra were recorded on a Bruker DRX500 MHz spectrometer (Bruker; Z ich, Switzerland). An Ostwald U-tube viscometer (Ambala, India) was made use of to measure the viscosity of PVC option in tetrahydrofuran (THF). The surface morphology of the PVC was inspectedPolymers 2021, 13,3 ofwith a Meiji Techno microscope (Tokyo, Japan), an Inspect S50 microscope (FEI Enterprise, Kohoutovice, Czech Republic), in addition to a Veeco instrument (Plainview, NY, USA) to supply the optical, scanning electron microscope (SEM), and atomic force microscopy (AFM) photos, respectively. The PVC weather influence was tested employing a QUV acceleration weather-meter analyzer (Q-Panel Business, Homestead, FL, USA). two.2. Synthesis of Nemonapride site complexes 1 and two A option of 4-methoxybenzoic acid (ligand; 0.76 g, 5 mmol) in methanol (MeOH; 50 mL) was added to a stirred option of triphenyltin chloride (Ph3 SnCl; 1.93 g, five.0 mmol) or tributyltin chloride (Bu3 SnCl; 1.63 g, five mmol) in MeOH (30 mL). The AZ3976 Biological Activity mixture was refluxed for 4 h and left to cool to room temperature. The strong obtained was filtered, washed with MeOH (2 20 mL), and dried to create 1 or two (Scheme 1) in 78 or 71 yields, respectively (Table 1). The structures of 1 and 2 have been confirmed by the FTIR and 1 H NMR spectra and the elemental analysis for the carbon, hydrogen, and tin contents (Table 1).Scheme 1. Synthesis of complexes 1 and 2. Table 1. Physical properties and analysis of complexes 1. Sn Complicated 1 2 three 4 R Ph Bu Bu Me Colour Off white White White Off white Yield ( ) 78 71 76 75 M.P. ( C) 15355 14446 14749 13638 Calculated (Found; ) C 62.31 (62.42) 54.45 (54.55) 53.86 (53.94) 47.93 (47.98) H 4.42 (five.48) 7.77 (7.80) six.03 (six.12) 4.47 (5.56) Sn 23.69 (23.52) 26.91 (26.75) 22.18 (22.04) 26.32 (26.24)2.3. Synthesis of Complexes 3 and four A option of your ligand (0.91 g, six mmol) in MeOH (50 mL) was added to a stirred solution of dibutyltin dichloride (Bu2 SnCl2 ; 0.91 g, three.0 mmol) or dimethyltin dichloride (Me2 SnCl2 ; 0.66 g, 3 mmol) in MeOH (30 mL). The mixture was refluxed for 4 h and left to cool to room temperature. The obtained solid was filtered, washed with MeOH (two 20 mL), and dried to produce three or 4 (Scheme 2) in 76 or 75 yields, respectively (Table 1). The structures of 3 and four were confirmed by the FTIR and 1 H NMR spectra and the elemental analysis for the carbon, hydrogen, and tin contents.Scheme two. Synthesis of complexes 3 and 4.Polymers 2021, 13,4 of2.four. Preparation of PVC Thin Films Films of pure PVC and also the material containing tin complexes of 4-methoxybenzoic acid have been ready based on the casting process at 25 C [36]. The polymer (5 g) was dissolved in THF (one hundred mL) at 25 C for 10 min. The Sn complexes (25 mg) had been added to the PVC answer. The mixture was stirred for 2 h to ensure the total homogeneity of your answer. The mixture was cast onto a glass dish (four four cm2 ) containing holes using a thickness of ca. 40 . The THF was evaporated at 25 C for 16 h to produce a film at the bottom in the glass dish. The traces of solvent trapped inside the blends have been removed applying a vacuum oven (16 h; 25 C) to produce dry, thin films.
