The nitration of 5,7-dimethyl-2-polyhaloalkylchromones affords either 5,7-dimethyl-6-nitro- or 5,7-dimethyl-6,8-dinitro-2-polyhaloalkylchromones, depending on the reaction conditions. Signals in the H-1 and C-13 NMR spectra of the sterically hindered chromones were completely assigned using the 2D NOESY, HETCOR, and COLOC spectra. The influence of nonplanar nitro groups on chemical shifts of carbon atoms was studied. Some spectral peculiarities of the peri-methyl group were revealed. The H-1-H-1 and C-13-H-1 spin-spin coupling constants, including the extreme six-bond long-range coupling between the protons of the Me(5) group and H(8), were determined.
Condensation of nitriles of polyhalogenated carboxylic acids and benzonitrile with 2-hydroxy-4,6-dimethylacetophenone
作者:V. Ya. Sosnovskikh
DOI:10.1007/bf02498966
日期:1998.2
Condensation of 2-hydroxy-4,6-dimethylacetophenone with trifluoro- and trichloroacetonitriles gives 2-amino-5,7-dimethyl-2-trifluoro(trichloro)methyl-4-chromanones. The condensation with 2,2,3,3-tetrafluoropropionitrile, perfluorovaleronitrile, and benzonitrile stops at the stage of formation of the corresponding enamines.
Synthesis of 2-(2-hydroxyaroylmethylene)hexahydropyrimidines from 2-trichloromethylchromones and trimethylenediamine
作者:V. Ya. Sosnovskikh、V. A. Kutsenko
DOI:10.1007/bf02494859
日期:1999.11
The reactions of 2-trichloromethylchromones with trimethylenediamine in ethanol at room temperature afford 2-(2-hydroxyaroylmethylene)hexahydropyrimidines. Under analogous conditions, 2-methylchromone gives a mixture ofN,N′-trimethylenebis[3-amino-1-(2′-hydroxyphenyl)-2-buten-1-one] andN,N′-trimethylenebis(imine) of 2-hydroxyacetophenone.