Sodium Hydroxide → HCID 49783989, compound

Participants

Reaction Steps

To a solution of ethyl and methyl esters of 3-[(dimethylamino)diazenyl]-4,5,6,7-tetrahydrobenzo[2,1-d]selenophene-2-carboxylate (1.0 g, 3.1 mmol) prepared as described in Example 5 step c) in methanol (10 mL) was added a solution of sodium hydroxide (500 mg, 12.6 mmol) in water (2 mL) and stirred at rt for 5 h. The mixture was diluted with ice cold water and extracted with chloroform (2×50 mL) to remove impurities. The aqueous layer was acidified with dil. HCl and stirred for 30 min. The solution was extracted with chloroform (3×100 mL) and the combined organic layer was washed with water, brine and dried over sodium sulfate. The solution was filtered and evaporated the solvent (550 mg, 57%). The crude product was recrystallized from chloroform-diethyl ether to give the product as a dark brown color solid (330 mg), mp 100-102° C. IR (Neat) νmax 3429, 2927, 2855, 1701, 1350, 1110, 1050, 1023, 880 cm−1; 1H NMR (400 MHz, CDCl3): δ 12.71 (1H, br s, —COOH), 3.59 (3H, s, —NCH3), 3.20 (3H, s, —NCH3), 2.83 (2H, t, J=5.4 Hz, H-4), 2.73 (2H, t, J=5.6 Hz, H-7), 1.75-1.81 (4H, m, H-5,6); 13C NMR (100 MHz, CDCl3): δ 164.5, 151.3, 148.9, 131.5, 124.0, 44.1, 36.5, 28.8 (2C), 22.8, 22.4; LC-MS (positive ion mode): m/z 300, 302 (M+H)+.

Provenance & Evidence