Simple method for the synthesis of amides

Abstract

Insulation was packed around the sides of the dish and the sample was then irradiated for 20 hr with the Hanovia arc (Pyrex filter) placed 4 in. above the top of the dish. The crude product was dissolved in 20 ml of hot benzene and filtered to remove insoluble tar. Cyclohexane (80 ml) was added, and the solution was heated to boiling, treated with Darco, and again filtered. The filtrate was cooled to room temperature and then overnight at 10°to yield 250 mg (14.6%) of pale yellow crystals. Recrystallization from benzene-cyclohexane gave crystals: mp 185.5-186.5°; nmr (CDCU) i 2.57 (m, CH2CH2),4.2 (2H,m,CHAr),and7.1 and 7.95 (8 H, 2 d, / = 8.5 Hz, 4-nitrophenyls); mass spectrum (50 eV, direct inlet) m/e (relative intensity) 298 (2.2), 270 (0.5),

Two Ways of Preparing Benzonitriles Using BrCCl3–PPh3 as the Reagent

“…IR spectra were measured with a Thermo/Nicolet Nexus 470 FT-IR ESP Spectrometer. 1 H and 13 C NMR spectra were recorded with a Varian 400 NMR ( 1 H at 395.7 MHz, 13 27,28 were obtained by reacting 4-hydroxybenzaldehyde and salicylamide, respectively, with the appropriate alkyl halide (i, NaOH, DMSO; ii, alkylbromide or iodide). Benzamide, 3-chlorobenzamide and 4-nitrobenzamide were made by hydrolysis of benzonitrile, 3-chlorobenzonitrile and 4-nitrobenzonitrile, respectively (i, conc.…”

Chiral pyridine N-oxides: useful ligands for asymmetric catalysis

“…Oxidation of these acids with hydrogen peroxide in AcOH gave the corresponding N-oxides 102 and 105 in good yields (76-79%). The condensation of these N-oxides with L L -amino acid esters or (1R,2S)-norephedrine, carried out employing bromotrichloromethane/triphenylphosphine for the activation of the carboxylic acids, 39 gave the desired chiral amides in moderate yields (30-59%). For a comparison, the 2,6-bis(aminoacyl)pyridines 107d and 107e were prepared by converting 104 into the 2,6-diacyl chloride, which was next treated with methionine methyl ester or norephedrine, respectively (Scheme 28).…”

Preparation, Investigation and Theoretical Study of α-chloroacetamide-N-(p-substituted) phenyl

“…Refluxing carboxylic acid, triphenyl phosphine, bromo tri-chloro methane, and an amine give rise to the corresponding amide [6], as shown below: This reaction presumably proceeds via acyl chloride, because it is known that triphenyl phosphine and CCl 4 converts the carboxylic acid to the corresponding acyl chloride [7] PPh 3 and N-bromosuccinimide generate acyl bromide [8].…”