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3. Synthesis of 2-chloromethyl-5-phenylthieno[2,3-d]pyrimidin-4(3H)-one (Viii)Part-IIExperimentalA mixture of ethyl 2-amino-4-phenylthiophene 3-carboxylate (Iv, 4.94 gm; 0.02 mole),chloroacetonitrile (1.65 gm; 0.022 mole) and catalytic amount of HCl (0.5 ml) werereacted under microwave irradiation (20 min) as per procedure described for thecompound Vi. The crude product on recrystallization from methanol-chloroform mixtureyielded the 2-chloromethyl-5-phenylthieno[2,3-d]pyrimidin-4(3H)-one (Viii).M.P. : 220-222 o C (221-223 o C) 2 ; Yield: 75%Mol. Formula : C 13 H 9 ClN 2 OS; Mol. Wt. 276.74IR (KBr) cm -1 : 2855(γ C-H ), 1660(γ C=O ), 748(γ C-Cl )1 H NMR (CDCl 3 )δppm : 4.58 (2H, s, CH 2, ), 7.31-7.52 (5H, m, Ar-H and 1H at 6position), 12.69 (1H, s, br, NH);4. Synthesis of ethyl 2-chloromethyl-3,4-dihydro-5-methyl-4-oxothieno[2,3-d]-pyrimidine 6-carboxylate (Viv)A mixture of diethyl 5-amino-3-methylthiophene-2,4-dicarboxylate (Iiii, 5.14 gm; 0.02mole), chloroacetonitrile (1.65 gm; 0.022 mole) and catalytic amount of HCl (0.5 ml)were reacted under microwave irradiation (27 min) as per procedure described for thecompound Vi. The crude product on recrystallization from methanol-chloroform mixtureyielded the ethyl 2-chloromethyl-3,4-dihydro-5-methyl-4-oxothieno[2,3-d]pyrimidine 6-carboxylate (Viv).M.P. : 241-243 o C (243-246 o C) 2 ; Yield: 90%Mol. Formula : C 11 H 11 ClN 2 O 3 S; Mol. Wt. 286.73IR (KBr) cm -1 : 2864(γ C-H ), 1725(γ C=O ), 1670(γ CONH ), 763(γ C-Cl )1 H NMR (CDCl 3 )δppm : 1.41 (3H, t, J = 7, CH 3 ), 2.95 (3H, s, CH 3 ), 4.38 (2H, quartlet, J= 7, CH 2 ), 4.57 (2H, s, CH 2 ), 10.62 (1H, s, NH)5. Synthesis of 2-chloromethyl-5,6,7,8-tetrahydrobenzo(b)thieno[2,3-d]pyrimidin-4(3H)-one (Vv)A mixture of ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene 3-carboxylate (Ii, 4.5gm; 0.02 mole), chloroacetonitrile (1.65 gm; 0.022 mole) and catalytic amount of HCl(0.5 ml) were reacted under microwave irradiation (10 min) as per procedure describedfor the compound Vi. The crude product on recrystallization from methanol-chloroform364