* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
With hydrogenchloride; sodium chloride In tetrahydrofuran; water
A/Preparation of 3-Bromo-2-hydroxymethyl-thiophene: 2-(3-Bromothienyl)carboxylic acid (7 g; 34 mmoles) is dissolved in 25 ml of anhydrous THF. A solution of aluminium hydride AlH3 in anhydrous THF (2 M; 42 ml; 84 mmoles) is added slowly at a temperature of 0° C. At the end of the addition, the reaction mixture is refluxed for 3 hours. After cooling to 0° C., water (200 ml) and hydrochloric acid (1N, 150 ml) are added. The mixture is decanted and the aqueous phase extracted with 3*150 ml of tert-butyl methyl ether. The organic phases are combined and then washed with 150 ml of a saturated solution of sodium chloride, dried over magnesium sulphate and filtered. The solvent is evaporated under reduced pressure. The desired product is obtained as a brown oil and is used as such in the next step. Yield: 95percent; Physical characteristics: * NMR1H: (CD3OD) 4.69 ppm (s; 2H); 6.95 ppm (d; 1H, J=5.2 Hz); 7.39 ppm (d; 1H, J=5.2 Hz). * NMR13C: (DMSO-d6) 57.80 ppm; 106.28 ppm; 126.11 ppm; 129.80 ppm; 141.15 ppm. * MS: (EI, 70 eV); 194/192 (M+*; 80percent); 177/175 (30percent); 113 (50percent); 98 (60percent); 85 (100percent).
73%
With sodium hydroxide; borane In tetrahydrofuran; methanol; (2S)-N-methyl-1-phenylpropan-2-amine hydrate
b. 3-Bromo-2-thiophenemethanol A stirred, ice-water chilled solution of 90.0 g of 3-bromo-2-thiophenecarboxylic acid and 600 ml of sieve dried tetrahydrofuran was treated at 5° C. with 962 ml of borane in tetrahydrofuran (1.04M solution) over 2 hours (nitrogen atmosphere), with exclusion of moisture. The stirred solution and cooling bath were allowed to equilibrate to ambient temperature overnight. The stirred, chilled (10° C.) solution was treated dropwise with 150 ml methanol over 2 hours and then with 100 ml of 10percent sodium hydroxide. After concentration, the residue was diluted with water, adjusted to pH=8 with 10percent sodium hydroxide solution and extracted with ether (2*300 ml). The combined dried (over anhydrous sodium sulfate) ethereal phase was concentrated. Distillation gave 61 g (73percent) of product, b.p. 79°-82° C. (0.38 mm). Analysis: Calculated for C5 H5 BrOS: 31.11percentC; 2.61percentH. Found: 31.30L percentC; 2.70percentH.
Chemistry
Pharmaceutical Intermediates
Inhibitors/Agonists
Material Science
For Research Only
120K+ Compounds
Competitive Price
1-2 Day Shipping
