A remote β,γ-regioselective asymmetric inverse-electron-demand oxa-Diels–Alder reaction between allylic ketones and α-cyano-α,β-unsaturated ketones has been developed through induced extended dienamine catalysis of a cinchona-derived primary amine. A spectrum of densely substituted dihydropyran frameworks were efficiently produced with excellent enantioselectivity and fair to exclusive diastereoselectivity
Alumina supported potassium fluoride promoted reaction of nitroalkanes with electrophilic alkenes : synthesis of 4,5-dihydro furans and isoxazoline n-oxides
作者:Jean Marie Mélot、Francoise Texier-Boullet、André Foucaud
DOI:10.1016/s0040-4020(01)81729-4
日期:1988.1
The reaction of secondary nitro alkanes 1 with α,β-unsaturated ketones 2 in the presence of alumina-supported potassiumfluoride in acetonitrile gave 4,5-dihydrofurans 3 in high yields ; 1-nitropropane reacted with 2 to give a mixture of 4,5-dihydrofurans and furans. Nitroalkenes 17 reacted with nitroalkanes to give isoxazoline N-oxides 18 and 19 in good overall yields.
Synthesis and Studies of Some Ketosulfones, Part I
作者:D. Aleksiev、S. Ivanona、G. Jekova
DOI:10.1080/10426500500366236
日期:2006.6.1
New ketosulfones have been prepared. Their chemical composition and structure were proved by analytical and spectral methods. The kinetics of 1,4-addition of arenesulfinic acids to 1,3-diphenyl-2-nitropropenone and 3-nitro-4-phenyl-3-butene-2-on were studied by LC. The overall reaction is second order, while it is first order regarding each reagent and substrate. On the basis of the experimental results
Nitropyridines. 2. Hantzsch Synthesis of Nitro- and Dinitropyridines
作者:G. P. Sagitullina、L. V. Glizdinskaya、R. S. Sagitullin
DOI:10.1007/s10593-005-0214-4
日期:2005.6
Nitropyridines: III. Synthesis of meta-terphenyls by recyclization of nitropyridinium salts
作者:G. P. Sagitullina、L. V. Glidzinskaya、R. S. Sagitullin
DOI:10.1134/s1070428006080173
日期:2006.8
A two-component Hantzsch synthesis was applied to preparation of nitropyridines and their quaternary salts from various enamines and chalcones based on nitroacetophenone. The recyclization of nitropyridinium quaternary salts under the treatment with an aqueous-alcoholic alkali led to preparation of 5'-methylamino-2'-nitro-m-terphenyl derivatives.