DBU-catalyzed one-pot cascade reaction of propargylamines and water for the synthesis of flavanones has been developed. This process proceeds via a sequence of 1,4-conjugate addition of water to alkynyl o-quinone methide (o-AQM), followed by the alkyne–allene isomerization and subsequent intramolecular oxa-Michael addition. This strategy provides a convenient method for accessing a broad range of flavanones
Abstract A facile ethylenediamine diacetate (EDDA)-catalyzed one-pot synthesis of biologically interesting flavanone derivativesfrom 2-hydroxyacetophenones, aromatic aldehydes, and aniline via a Mannich-type reaction is described. This synthetic method provides a rapid access to biologically interesting flavanone derivatives. To demonstrate this method, several biologically interesting natural products
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.
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.
Simple and Efficient One Step Synthesis of Functionalized Flavanones and Chalcones
作者:ABDULLAH SAAD ALBOGAMI、USAMA KARAMA、AHMED AMINE MOUSA、M. KHAN、SARA ABDULLAH AL-MAZROA、HAMAD Z. ALKHATHLAN
DOI:10.13005/ojc/280201
日期:2012.6.18
A facile and highly efficient microwave-assisted synthesis of functionalizedchalcones and flavanones based on the Claisen-Schmidt condensation reaction is reported. The method describes the synthesis of flavanones in single step with excellent yield and it was revealed that position and number of substituents on acetophenones and aromatic aldehydes played a very crucial and key role in the construction