A protocol for the synthesis of C5-olefinated 2-arylchromanones in a regio- and stereoselective fashion through the ruthenium-catalyzed oxidative coupling of diversified 2-arylchromanones with various alkenes through a keto-directed, site-selective C–Hactivation reaction is developed. IBO = isobornyl.
Hypervalent Iodine Oxidation of Flavanones: A New Synthesis of Methyl 2-Aryl-2,3-dihydrobenzofuran-3-carboxylates by 1,2-Aryl Shift
作者:Om Prakash、Madan P. Tanwar
DOI:10.1246/bcsj.68.1168
日期:1995.4
Flavanones (1), on oxidation with (diacetoxyiodo)benzene-sulfuric acid (DIB–H2SO4) or (hydroxy)tosyloxy)iodo)benzene (HTIB) in trimethyl orthoformate, undergo facile ring contraction by 1,2-aryl shift, thereby yielding methyl 2-aryl-2,3-dihydrobenzofuran-3-carboxylates (4) as major products (40—80%). cis-3-Methoxyflavanones (5) and flavones (3) are the minor products formed in variable ratios.
Highly diastereoselective Michael reaction under solvent-free conditions using microwaves: conjugate addition of flavanone to its chalcone precursor
作者:Tamás Patonay、Rajender S Varma、András Vass、Albert Lévai、József Dudás
DOI:10.1016/s0040-4039(00)02264-4
日期:2001.2
Microwave-assisted reaction of 2′-hydroxychalcones in the presence of DBU resulted in the formation of hitherto unknown dimers by conjugateaddition of the intermediate cyclic ketone to the starting enone.
Oxidative 1,2-aryl rearrangement in flavanones using thallium(III) -tolylsulphonate (TTS)= A new useful route to isoflavones
作者:Om V. Singh、C.P. Garg、R.P. Kapoor
DOI:10.1016/s0040-4039(00)94689-6
日期:1990.1
Oxidation of flavanones usingthallium(III) -tolylsulphonate (prepared by the reaction of thallium(III) acetate and -toluene sulphonic acid) in propionitrile leads to 1,2-aryl shift providing a new useful route to the synthesis of isoflavones.
Synthesis of 5-aryl-2-piperidino-5H-chromeno[3,4-c]pyridine-1-carbonitriles
作者:M. Venkati、S. Satyanarayana Reddy、G. Y. S. K. Swamy、K. Ravikumar、G. L. David Krupadanam
DOI:10.3998/ark.5550190.0013.632
日期:——
Chloro-2-aryl-2H-3-chromenecarbaldehydes 3a-g on reaction with malononitrile in ethanol in the presence of piperidine gave 5-aryl-2-piperidino-5H-chromeno(3,4-c)pyridine-1-carbonitriles 4a-g in good yields.