| |
[摘要]：A green and convenient approach to the synthesis of a series of 4,7-diaryl-5-oxo-4H-benzo[b]pyran derivatives from appropriate aromatic aldehydes and 5-aryl-1,3-cyclohexanedione with malononitrile in the presence of dilute HCl as catalyst (30 mmol/L) is described. This method provides several advantages such as environmental friendliness, low cost, high yields, and simple work up procedure. The structures of all compounds were characterized by infrared (IR), mass spectrometry (MS), 1H NMR, and elemental analysis. The crystal structure of trans/cis-2-amino-3-cyano-7-(4'-methoxo-phenyl)-4-phenyl-5-oxo-4H-benzo[b]pyran, g, was determined by single crystal X-ray diffraction analysis. The crystal of compound g belongs to monoclinic with space group P 21/c, a = 8.477(3) nm, b = 18.948(6) nm, c = 24.915(7) nm, a = 90.00 degrees, beta = 107.388(11)degrees, ?= 90.00 degrees, Z = 8, V = 3.819(2) nm3, R1 = 0.0754, wR2 = 0.2042. |
|
