Nitromethane as a surrogate cyanating agent: 7-N,N-dimethylamino-4-hydroxycoumarin-catalyzed, metal-free synthesis of α-iminonitriles

Abstract

An efficient, metal/alkali-cyanide free approach for the synthesis of α‐iminonitriles via kinetically controlled, base-mediated and 1,3-diketone-catalyzed reaction is reported. The preparation of target compounds was realized by condensation of substituted...

Chemistry of (E)‐2‐(2,4‐Dioxochroman‐3‐ylidene)‐2‐phenylacetonitrile: Access to Biscoumarin‐Fused Trioxabicycles

“…Scheme 1 depicts the unanticipated two-step synthesis of biscoumarin-fused trioxabicycle 7 a. Aiming to prepare (E)-2-(2,4-dioxochroman-3-ylidene)-2-phenylacetonitrile (8) and subsequent investigation of its intrinsic chemical reactivity (Scheme 1), [13] we followed the literature procedure for the preparation of 2-(2,2,2-trifluoro-1-aryl-ethylidene)cyclohexane-1,3-dione reported by Lal and coworkers, [14] except that the starting material 2',2',2'-trifluoroacetophenone was replaced with benzoyl cyanide, as shown in Scheme 1. The synthesis started with coupling of 4-hydroxycoumarin (9) with benzoyl cyanide (10) in the presence of potassium carbonate as a base in acetonitrile for 24 h to give the proposed alcohol 11.…”

“…Highresolution mass spectra (HRMS) were obtained on a Thermo Fisher Scientific Finnigan MAT95XL spectrometer using a magnetic sector analyzer. 1 H NMR (400 MHz) and 13 C NMR (100) spectra were recorded on a Bruker 400 spectrometer. Chemical shifts were reported in parts per million on the scale relative to an internal standard (tetramethylsilane, or appropriate solvent peaks) with coupling constants given in hertz.…”

“…7, 5]dioxocino [3,2-c:7,6-c'] -7,15-diphenyl-7,15-epoxy[1,5]dioxocino [3,2-c:7,6c']dichromene-6,14(7H,15H)-dione (7 c). R f = 0.5 (10% EtOAc/hexanes); white solid; 99 mg; yield 67%; mp 304-306 °C; 1 H NMR (CDCl 3 , 400 MHz) δ 8.12 (d, J = 2.4 Hz, 2H), 7.86-7.83 (m, 4H), 7.61 (dd, J = 8.8, 2.4 Hz, 2H), 7.50-7.49 (m, 6H), 7.27 (d, J = 8.0 Hz, 2H); 13…”

“…. R f = 0.5 (10% EtOAc/ hexanes); white solid; 115 mg; yield 67%; mp 292-294 °C; 1 H NMR (CDCl 3 , 400 MHz) δ 8.24 (d, J = 2.0 Hz, 2H), 7.83-7.81 (m, 2H), 7.63-7.57 (m, 8H), 7.25 (d, J = 8.8 Hz, 2H); 13 C{ 1 H} NMR (CDCl 3 , 100 MHz) δ 160.9, 157.6, 153.9, 135.0, 134.1, 130.0, 128.5, 128.…”

New Insights Into the Promising Antibacterial Activity of Thiophene or Chromene Moiety Containing Aryl Sulfonamide

“…126 A number of pathways are available for their synthesis, but there is a signi cant need for approaches that include chromenes from precursors that are readily available. 127 Some synthesized sulfonamide derived chromenes were investigated for antibacterial, antifungal and cytotoxic. 128 Chromone is known as a single molecule that can be paired with various receptors groups.…”