Materials and methodsAniline derivatives, p-nitrophenol, 2-naphthol, formaldehyde, FeCl3,6H2O, FeCl2,4H2O, ammonia, tetra ethylene pentamine, epichlorohydrin and chlorosulfonic acid were obtained from Merck and Aldrich company. The surface morphology of catalyst was characterized by FESEM instrument (Mira3-XMU). The crystalline structure of catalyst was obtained with Philips X’pert MPD diffractometer. FT-IR spectra were recorded using PerkinElmer 781 spectrophotometer and KBr pellets to determine the functional groups in the range of 400–4000 cm−1. For more confirmation of [1,3]-oxazines structure, Bruker 1H NMR and 13C NMR on DRX-400 spectrometer were applied. Thermal weighing analysis was obtained with the DuPont 2000 TGA V5.1A device.Synthesis of catalystSynthesis of magnetic Ferrierite nanoparticles (M-FER)1 g of ferrierite was poured into a 50 ml round bottom flask and 1.5 g of FeCl3. 6H2O, 0.75 g of FeCl2. 4H2O, and 10 ml of deionized water was added. Then, ammonia (32%) was added dropwise under N2 atmosphere until black precipitate was formed and stabilized on the ferrierite surfaces. The obtained mixture was stirred for 1 h at room temperature and then, separated with a strong magnet, washed with DI water and dried in at 80 °C (Scheme 2).Scheme 2.The preparation of magnetic solid acid nanocatalyst based on ferrierite (M-FER/TEPA/SO3H).Modification of magnetic Ferrierite nanoparticles by epichlorohydrin linker (M-FER/ECH)1 g of M-FER, 2.27 ml of epichlorohydrin and 2 ml of ethanol were added to a 50 ml flask and stirred at 60 °C for 24 h by a magnetic stirrer. Afterwards, the mixture was centrifuged to separate the M-FER/ECH. Then, the nanoparticles were washed twice with ethanol and at the end, was dried at 80 °C (Scheme 2).Modification of M-FER/ECH by tetra ethylene pentamine (M-FER/ECH/TEPA)To attach TEPA on M-FER/ECH nanoparticles, 0.7 g of the modified substrate from the previous step (M-FER/ECH), along with 20 ml of toluene were poured into a 50 ml flask placed in an ultrasonic bath for 10 min. Then, 1 ml of TEPA was added and the reaction was performed at 100 °C for 24 h under nitrogen atmosphere. After the time, functionalized nanoparticles were separated by an external magnetic field and washed twice with ethanol and finally dried at 80°C (Scheme 2).Preparation of Solid acid catalyst nanoparticles based on Ferrierite M-FER/ECH/TEPA/SO3HTo prepare the solid acid catalyst, 0.5 g of the FER/ECH/TEPA obtained from the previous step, with 10 ml of dichloromethane was added to a 50 ml flask and dispersed in the ultrasonic bath for 20 min. After that, 1.5 ml of chlorosulfonic acid was added dropwise to the reaction mixture during 20 min under a laboratory fume hood and then, stirred for 3 h at room temperature using a magnetic stirrer. At the end, the produced nanoparticles were separated by a magnet and washed with dichloromethane and ethanol and dried (Scheme 2). The acidic site of solid acid catalyst was determined by back titration method. According to obtained results, the concentration of catalytic sites (H+) was 0.95 mmol.g-1.Synthesis of [1,3]-oxazine derivatives in the presence of (M-FER/TEPA/SO3H)A mixture of β-naphthol/p-nitrophenol (1 mmol), formaldehyde (2 mmol) and aniline derivatives (1 mmol) were added to 2 ml of distilled water and mixed at room temperature in the presence of 0.015 g of the prepared catalyst (the reaction progress was monitored by TLC during all stages of the reaction). After completion of the reaction, the catalyst was separated with strong magnet, washed with ethanol and water and dried for other reactions. The pure product was obtained by filtration of reaction mixture and washed with ethanol and water and dried at 80° (Scheme 1).Representative spectral data2-(4-chlorophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4a)FTIR (KBr) ῡ (cm−1): 3437, 2915, 2857, 1624, 1491, 1394, 1225, 1002, 1181, 812; 1H NMR (400 MHz, CDCL3, δ, ppm): 4.95 (s,2H, Ar-CH2-N), 5.42 (s,2H, O-CH2-N), 7.05–7.12 (m, 4H, Ar-H), 7.23 (d, J = 8.9 Hz, 1H, Ar-H), 7.41 (t, J = 8.1 Hz, 1H, Ar-H), 7.55 (t, J = 7.5 Hz, 1H, Ar-H), 7.69 (t, J = 7.7 Hz, 2H, Ar-H), 7.80 (d, J = 7.8 Hz, 1H, Ar-H).2-(4-Bromophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4b)FT-IR (KBr) ῡ (cm−1): 3425, 1629, 1483, 1390, 1223, 1001, 1180, 810; 1H NMR (400 MHz, CDCL3, δ, ppm): 4.95 (s,2H, Ar-CH2-N), 5.42 (s,2H, O-CH2-N), 7.05 (d, J = 9.0 Hz, 2H, Ar-H), 7.39–7.43 (m, 4H, Ar-H), 7.55 (t, J = 8.3 Hz, 1H, Ar-H), 7.69 (t, J = 8.7 Hz, 2H, Ar-H), 7.80 (d, J = 8.2 Hz, 1H, Ar-H).2-(4-Iodophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4c)FT-IR (KBr) ῡ (cm−1): 3428, 3257, 2924, 2858, 1626, 1479, 1398, 1237, 1117, 810; 1H NMR (400 MHz, CDCl3 δ ppm): 5.01 (s,2H, Ar-CH2-N), 5.35 (s,2H, O-CH2-N), 6.66 (d, J = 8.7 Hz, 4H, Ar-H), 7.15 (d, J = 8.8 Hz, 2H, Ar-H), 7.80 (t, J = 6.9 Hz, 2H, Ar-H), 7.82 (d, J = 8.2 Hz, 1H, Ar-H), 7.90 (d, J = 8.6 Hz, 1H, Ar-H); 13C NMR (100 MHz, CDCl3 δ ppm): 30.68, 37.48, 114.93, 114.96, 115.01, 118.08, 122.46, 123.12, 126.37, 128.14, 128.16, 129.02, 133.56, 136.98, 148.42, 153.09.2-(3-Chloro-4- Fluorophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4d)FT-IR (KBr) ῡ (cm−1): 3440, 2950, 2897, 1602, 1498, 1395, 1227, 1002, 1147, 947, 814; 1H NMR (400 MHz, CDCl3 δ ppm):4.93 (s,2H Ar-CH2-N), 5.37 (s,2H O-CH2-N), 7.00–7.09 (m, 3H, Ar-H), 7.23 (d, J = 7.7 Hz, 1H, Ar-H), 7.42 (t, J = 7.0 Hz, 1H, Ar-H), 7.55 (t, J = 7.0 Hz, 1H, Ar-H), 7.7 (dd, J = 8.7,3.4 Hz, 2H, Ar-H), 7.82 (d, J = 8.1 Hz, 1H, Ar-H); 13C NMR (100 MHz, CDCl3 δ ppm): 30.42, 48.35, 79.05, 111.38, 115.37, 116.15, 116.41, 118.19, 120.27, 120.56, 123.39, 126.40, 128.08, 128.28, 128.63, 130.62, 145.27, 151.45.2-(4- Methoxyphenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4e)FT-IR (KBr) ῡ (cm−1): 3333, 3055, 2925, 2862, 1588, 1510, 1456, 1387, 1241, 1181, 811; 1H NMR (400 MHz, CDCl3 δ ppm): 3.77 (s,3H, CH3), 4.92 (s,2H, Ar-CH2-N), 5.38 (s,2H, O-CH2-N), 6.83 (d, J = 9.1 Hz, 2H, Ar-H), 7.07 (d, J = 8.9, 1H, Ar-H), 7.13 (d, J = 9.0, 2H, Ar-H), 7.40 (t, J = 6.9 Hz, 1H, Ar-H), 7.53 (t, J = 7.0 Hz, 1H, Ar-H), 7.69 (t, J = 8.5 Hz, 2H, Ar-H), 1.02 (d, J = 7.5 Hz, 1H, Ar-H).2-(4- Nitrophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4f)FT-IR (KBr) ῡ (cm−1): 3431, 2921, 1600, 1478, 1394, 1321, 1265, 1010, 1191; 1H NMR (400 MHz, CDCl3 δ ppm): 5.09 (s,2H, Ar-CH2-N), 5.53 (s,2H, O-CH2-N), 7.12 (d, J = 8.9 Hz, 1H, Ar-H), 7.18 (d, J = 9.3 Hz, 2H, Ar-H), 7.45 (t, J = 7.6 Hz, 1H, Ar-H), 7.60 (t, J = 7.1 Hz, 1H, Ar-H), 7.73 (t, J = 8.5 Hz, 2H, Ar-H), 7.84 (d, J = 8.1 Hz, 1H, Ar-H), 8.22 (d, J = 9.4 Hz, 2H, Ar-H).2-(3- Nitrophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4g)FT-IR (KBr) ῡ (cm−1): 3429, 3085, 3015, 2894, 1592, 1493, 1380, 1349, 1230, 1105, 1008; 1H NMR (400 MHz, CDCl3 δ ppm): 5.06 (s,2H, Ar-CH2-N), 5.51 (s,2H, O-CH2-N), 7.08 (d, J = 8.9 Hz, 1H, Ar-H), 7.52–7.39 (m, 3H, Ar-H), 7.57 (t, J = 7.8 Hz, 1H, Ar-H), 7.85–7.66 (m, 4H, Ar-H), 8.04 (s, 1H, Ar-H).2-(2- Nitrophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4h)FT-IR (KBr) ῡ (cm−1): 1621, 1575, 1510, 1430, 1390, 1341, 1274, 1232, 1157; 1H NMR (400 MHz, CDCl3 δ ppm): 4.48 (s, 2H, Ar-CH2-N), 5.04 (s, 2H, O-CH2-N), 6.71 (t, J = 7.6 Hz, 1H, Ar-H), 6.82–6.86 (m, 4H, Ar-H), 7.03 (d, J = 8.5 Hz, 2H, Ar-H), 7.23 (d, J = 8.6 Hz, 1H), 7.38 (t, J = 7.6 Hz, 1H, Ar-H), 7.54 (t, J = 8.5 Hz, 1H, Ar-H).2-(2,4- Dinitrophenyl)-3,2-dihydro-1H-naphtho[1,2-e] [1,3]-oxazine (4i)FT-IR (KBr) ῡ (cm−1): 1629, 1500, 1423, 1333, 1263, 919, 1122; 1H NMR (400 MHz, CDCl3 δ ppm): 6.22–6.88 (m, 4H, 2CH2), 6.93 (d, J = 9.2 Hz, 2H, Ar-H), 7.28 (d, J = 3.6 Hz, 3H, Ar-H), 8.25 (dd, J = 9.2, 2.6 Hz, 2H, Ar-H), 9.14 (d, J = 2.6 Hz, 2H, Ar-H); 13C NMR (125 MHz, CDCl3 δ ppm): 38.76, 39.60, 118.05, 119.41, 119.70, 122.98, 123.27, 127.98, 128.31, 128.59, 128.89, 129.18, 134.77, 135.06, 149.49, 149.75, 151.40, 151.69.3-(3-Chloro-4-methylphenyl)-6-nitro-3-4-dihydro-2H-benzo[e] [1,3]-oxazine (6a)FT-IR (KBr) ῡ (cm−1): 3434, 1599, 1499, 1403, 1346, 1227, 1144, 941, 802; 1H NMR (400 MHz, DMSO-d6 δ ppm): 4.41 (s,2H, Ar-CH2-N), 4.92 (s,2H, O-CH2-N), 6.59–6.62 (m, 2H, Ar-H), 6.80 (s, 1H, Ar-H), 7.11 (t, J = 9.1Hz, 2H, Ar-H), 7.26 (d, J = 9.0 Hz, 1H, Ar-H); 13C NMR (125 MHz, DMSO-d6 δ ppm). 69.43, 76.78, 116.25, 116.47, 117.74, 117.97, 119.99, 120.18, 120.63, 120.82, 144.83, 144.78, 151.62, 154.06.3-(4-Boromophenyl)-6-nitro-3-4-dihydro-2H-benzo[e] [1,3]-oxazine (6b)FT-IR (KBr) ῡ (cm−1): 3429, 3039, 2929, 2846, 1592, 1493, 1380, 1330, 1226, 1162, 809; 1H NMR (400 MHz, CDCl3 δ ppm): 4.79 (s,2H, Ar-CH2-N), 5.09 (s,2H, O-CH2-O), 6.69 (dd, J = 6.3Hz, 2.3 Hz, 2H, Ar-H), 6.99 (d, J = 5.2 Hz, 2H, Ar-H), 7.16 (d, J = 9.1 Hz, 2H, Ar-H), 7.33 (s, 1H, Ar-H).
