2-(2-Ethoxyphenoxy)ethylamine

Reaction scheme: Step-1 Procedure: To a solution of Oxirane intermediate (1.0 g, 3.3 mmol) in iPrOH (20 ml), was added 2-ethoxy Phenoxy ethyl amine(0.89g, 4.92mmol). The reaction mixture was stirred under 60C for 16h, after that RM was concentrated under reduced pressure and purified by silica column chromatography using 1 % methanol in ethyl acetate as eluent to give (0.3 g, 18% ) as a thick liquid.(a) Synthesis of Oxalate Salt of Racemic Tamsulosin 2-(o-Ethoxyphenoxy)ethylamine (45 gm) was dissolved in methanol (250 mL). To this 2-methoxy-5-(2-oxopropyl)-benzene sulfonamide (55 gm), catalyst 5% platinum on carbon (12.1 gm) and methanol (330 mL) were added. The mixture was hydrogenated in autocalve at 55 C. at hydrogen pressure of 13 kg/cm2 for 5 hrs. The reaction mixture was cooled and the catalyst was filtered off. To the filtrate containing racemic tamsulosin, oxalic acid (14.3 gm) was added and the solvent was distilled off. To the residue, acetone (700 mL) was added and stirred at reflux temperature for 30 mins. The mixture was cooled, filtered, and the filter cake washed with acetone (50 mL). The salt was further purified by suspending the material in 2-propanol at reflux temperature, cooling to ambient temperature and filtering the solid. The pure oxalate salt of racemic tamsulosin shows a melting range of: 178-182 C. and HPLC purity: 97.24 (area %). The chiral HPLC showed it to be a mixture R and S isomers in the ratio of 50.1 to 49.9. The infrared spectrum of the oxalate salt of racemic tamsulosin as shown in of the drawing accompanying this specification, exhibited peaks at cm-1: 1154 & 1332 (SO2), 3408 (-NH2), 2983 (NH2+), 1591 (COO-). The 1H-NMR spectrum in CD3SOCD3 gave signals at 8 values: 1.06-1.08 (3H, d, >CH-), 1.30-1.33 (3H, t, -CH2-), 3.89 (3H, s, -O), 4.15-4.36 (10 H, 4-CH2, -CH, -NH), 7.61 (2H, s, -NH2), 6.8-7.5 (7H, m, Ar-H). The 13C-NMR spectrum exhibited signals as expected, in particular at delta values 56.34 (-OH3), 14.93 (-OCH2H3), 17.29 (-CH.H3), 54.59 (-H.CH3), 64.11 (-OH2.CH3), 44.51 (-NH.H2.CH2.CH2.O-), 67.25 (-NH.CH2.H2.O-), 39.53 (-H2.CH-), 165.35 (COOH oxalate). Element analysis: C=53.64% (Calcd. 53.49%), H=6.57% (Calcd. 6.62%), N=5.89% (Calcd. 5.95%) and S=6.58% (Calcd. 6.79%) and corresponds to the hydrate, M.Wt. 471.53, C21H29N2O7S.H2O. The ES-mass spectrum signal at m/z=409 corresponded to mass of free base. The XRD trace shows strong peaks at 2 theta values: 20.36, 22.33, 14.8, and 13.74 in that sequence as shown in . The DSC thermogram of pure salt exhibited a sharp peak at 180.2 C. as shown in4.87 g of 2-methoxy-5-(2-oxopropyl)benzenesulfonamide, 3.62 g of

Molecular Weight:181.23
XLogP3:1.1
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:5
Exact Mass:181.110278721
Monoisotopic Mass:181.110278721
Topological Polar Surface Area:44.5
Heavy Atom Count:13
Complexity:130
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes