2796 Maher
Asian J. Chem.
2-[6-(4-Chlorobenzyloxy)-2-naphthyliden-4-(4-
chlorophenyl)]-5-methyl-1,3-thiazole (5a): (C28H20N2OSCl2.
compound (5a-f). The mixture was refluxed (18-20) h. After
completion of the reaction, the product was cooled to room
temperature and the benzene was removed under vacuum [21].
The whole mass treated with saturated solution of sodium
bicarbonate until carbon dioxide evolution. The formed product
was filtered off and washed several times with water. The
product thus obtained was recrystallized from absolute ethanol
to get pure crystal of 6a-f (Scheme-IV).
m.w. = 474 ). Yield 70 %; m.p.: 150-152 °C; IR (KBr, νmax
,
cm–1): 3066.22 (C-H arom), 1616.4 (-HC=N), 1540.5 (C=C),
1262 (-O-CH2), 680.7 (C-S-C);1H NMR (CDCl3) δ ppm 1.92
(s.3H.-CH3), 4.82 (s.2H.OCH2), 7.08-7.98 (m.14H.arom). 9.2
13
(s.1H.-CH=N); C NMR (CDCl3) δ 33 (C-4), 61.4 (OCH2),
72 (C-3), 75.4 (C-2, 1), 77 (C-5), 132-129.7 (phenyl carbons),
138.9-129.00 (naphthyl carbons).
2-[6-(4-Chlorobenzyloxy)-2-naphthyliden-4-(4-
bromophenyl)]-5-methyl-1,3-thiazole (5b): (C28H20N2OSClBr;
N
S
CH
N
O
SH-CH2COOH
Benzene
m.w. = 518.5 ). Yield 72 %; m.p.: 156-158 °C; IR (KBr, νmax
,
S
cm–1): 3066.22 (C-H arom), 1616.4 (-HC=N), 1540.5 (C=C),
1262 (-O-CH2), 680.7 (C-S-C);1H NMR (CDCl3) δ ppm 1.92
(s.3H.-CH3), 4.82 (s.2H.OCH2), 7.08-7.98 (m.14H.arom). 8.9
(s.1H.-CH=N); 13C NMR (CDCl3) δ 33.8 (C-4), 61.8 (OCH2),
71.8 (C-3), 75.00 (C-2, 1), 77.5 (C-5), 131-129.2 (phenyl
carbons), 138.9-129.80 (naphthyl carbons).
N
S
R
N
O
(5a-f)
6a R = Cl
6b R = Br
R
Cl
6c R = F
O
6d R = NO2
6e R = CH3
6f R = OCH3
(6a-f)
2-[6-(4-Chlorobenzyloxy)-2-naphthyliden-4-(4-
fluorophenyl)]-5-methyl-1,3-thiazole (5c): (C28H20N2OSClF;
Cl
Scheme-IV: Synthesis of 2-{6-(4-chlorobenzyloxy)naphthyl)-3-[(4-substituted
phenyl)-5-methyl-1,3-thiazol-2-yl}thiazolidine-4-one (6a-f)
m.w. = 457.5 ). Yield 76 %; m.p.: 150-152 °C; IR (KBr, νmax
,
cm–1): 3065.2 (C-H arom), 1618.2 (-HC=N), 1542.3 (C=C),
1260 (-O-CH2), 682 (C-S-C);1H NMR (CDCl3) δ ppm 1.90
(s.3H.-CH3), 4.80 (s.2H.OCH2), 7.08-8.02 (m.14H.arom). 8.98
(s.1H.-CH=N); 13C NMR (CDCl3) δ 34.2 (C-4), 62.8 (OCH2),
71.6 (C-3), 73.7 (C-2, 1), 76.6 (C-5), 131-129.3 (phenyl
carbons), 138.02-129.44 (naphthyl carbons).
2-[6-(4-Chlorobenzyloxy)naphthyl-3-(4-chloride-
phenyl)-5-methyl-1,3-thiazol-2-yl]thiazolidin-4-one (6a):
Pale yellow solid; [Yield 65 %]; m.p.: 145-147 °C; IR (KBr,
ν
max, cm–1): 3042 (C-H arom), 1704 (C=O), 1540 (C=C), 1330
(-C-N), 1234 (-O-CH2), 680 (C-S-C); 1H NMR (CDCl3) δ ppm
1.84 (s.3H.-CH3), 3.94-4.10 (dd.2H.CH2), 4.46 (s.2H.OCH2),
5.9 (s.1H.S-CH-N), 7.2-8.20 (m.14H.arom); 13C NMR (CDCl3)
δ 31.2 (C-4, 6), 59 (OCH2), 62 (C-5, 3, 2), 73 (C-1), 114.5-
115.8 ( phenyl Carbons), 130.4-122.4 (naphthyl carbons)171
(C-7). Elemental analysis of (C30H22N2O2S2Cl2 m.w. = 577)
Calcd.. C, 62.35, H, 3.81, O, 5.55, N, 4.85, S, 11.09 found C,
62, 98, H.4.4, O, 6.1, N, 4.01, S, 10.42.
2-[6-(4-Chlorobenzyloxy)-2-naphthyliden-4-(4-nitro-
phenyl)]-5-methyl-1,3-thiazole (5d): (C28H20N3O3SCl; m.w.
= 484.5 ).Yield 76 %; m.p.: 170-172 °C; IR (KBr, νmax, cm–1):
3069.2 (C-H arom), 1620 (-HC=N), 1542.8 (C=C), 1264 (-O-
CH2), 687 (C-S-C), 1521-1344 (N-O);1H NMR (CDCl3) δ ppm
1.98 (s.3H.-CH3), 4.86 (s.2H.OCH2), 7.08-8.12 (m.14H.arom).
9.1 (s.1H.-CH=N); 13C NMR (CDCl3) δ 33.80 (C-4), 61.2
(OCH2), 73.4 (C-3), 76.1 (C-2, 1), 78 (C-5), 134-129.7 (phenyl
carbons), 138.2-129.09 (naphthyl carbons).
2-[6-(4-Chlorobenzyloxy)-2-naphthyliden-4-(4-methyl-
phenyl)]-5-methyl-1,3-thiazole (5e): (C29H23N2OSCl; m.w. =
453.5). [Yield 78 %; m.p.: 155-157 °C; IR (KBr, νmax, cm–1):
3064 (C-H arom), 1613 (-HC=N), 1536 (C=C), 1256 (-O-CH2),
678 (C-S-C);1H NMR (CDCl3) δ ppm 1.92 (s.3H.-CH3), 2.32
(s.3H.CH3-ph), 4.66 (s.2H.OCH2), 7.12-8.12 (m.14H.arom).
9.00 (s.1H.-CH=N); 13C NMR (CDCl3) δ 31.60 (C-4), 60.6
(OCH2), 70.60 (C-3), 73.20 (C-2, 1), 75.76 (C-5), 130-128.02
(phenyl carbons), 137.80-128.54 (naphthyl carbons).
2-[6-(4-Chlorobenzyloxy)-2-naphthyliden-4-(4-methoxy-
phenyl)]-5-methyl-1,3-thiazole (5f): (C29H23N2O2SCl; m.w.
= 469.5 ).Yield 71 %; m.p.: 177-179 °C; IR (KBr, νmax, cm–1):
3068 (C-H arom), 1611 (-HC=N), 1526 (C=C), 1258 (-O-CH2),
688 (C-S-C);1H NMR (CDCl3) δ ppm 1.88 (s.3H.-CH3), 2.30
(s.3H.CH3-O), 4.46 (s.2H.OCH2), 7.1-8.10 (m.14H.arom). 9.10
(s.1H.-CH=N); 13C NMR (CDCl3) δ 30.78 (C-4), 60.00
(OCH2), 70.65 (C-3), 73.14 (C-2, 1), 75.24 (C-5), 130-127.25
(phenyl carbons), 138.34-129.37 (naphthyl carbons).
Synthesis of 2-[6-(4-chlorobenzyloxy)naphthyl-3-(4-
substituted phenyl)-5-methyl-1,3-thiazol-2-yl]thiazolidin-
4-one (6a-f): (6m mol) of mercaptoacetic acid was added slowly
with stirring to the solution of (5 mmol) in 25 mL benzene
2-[6-(4-Chlorobenzyloxy)naphthyl-3-(4-bromo-
phenyl)-5-methyl-1,3-thiazol-2-yl]thiazolidin-4-one (6b):
Pale yellow solid; [Yield 60 %]; m.p.: 149-151 °C; IR (KBr,
ν
max, cm–1): 3052 (C-H arom), 1694 (C=O), 1530 (C=C), 1329
(-C-N), 1238 (-O-CH2), 687 (C-S-C); 1H NMR (CDCl3) δ ppm
1.86 (s.3H.-CH3), 3.80-3.99 (dd.2H.CH2), 4.50 (s.2H.OCH2),
6.1 (s.1H.S-CH-N), 7.12-8.20 (m.14H.arom); 13C NMR
(CDCl3) δ 31.5 (C-4, 6), 59.2 (OCH2), 61.1 (C-5, 3, 2), 72.8
(C-1), 114.2-115.6 ( phenyl Carbons), 129.8-122.3 (naphthyl
carbons)170 (C-13). Elemental analysis of (C30H22N2O2S2ClBr
m.w. = 621.5) Calcd.. C, 57.9, H, 3.54, O, 5.15, N, 4.51, S,
10.3 found C, 60.88, H.4.44, O, 6.03, N, 4.22, S, 10.62.
2-[6-(4-Chlorobenzyloxy)naphthyl-3-(4-fluoro-
phenyl)-5-methyl-1,3-thiazol-2-yl]thiazolidin-4-one (6c):
Pale yellow solid; [Yield 58 %]; m.p.: 140-142 °C; IR (KBr,
ν
max, cm–1): 3082 (C-H arom), 1702 (C=O), 1522 (C=C), 1321
(-C-N), 1232 (-O-CH2), 686 (C-S-C); 1H NMR (CDCl3) δ ppm
1.81 (s.3H.-CH3), 3.77-3.87 (dd.2H.CH2), 4.40 (s.2H.OCH2),
6.0 (s.1H.S-CH-N), 7.12-8.20 (m.14H.arom); 13C NMR
(CDCl3) δ 31.00 (C-4, 6), 58.2 (OCH2), 61.4 (C-5, 3, 2), 72.9
(C-1), 114.4-115.8 ( phenyl Carbons), 129.2-122.00 (naphthyl
carbons)170.4 (C-13). Elemental analysis of (C30H22N2O2S2ClF
m.w. = 559.5) Calcd.. C, 64.34, H, 3.96, O, 5.72, N, 5.00, S,
11.44 found C, 63.66, H.4.92, O, 6.45, N, 4.11, S, 10.64.