Enantioselective Synthesis of Unsymmetrical Diaryl-Substituted Spirocyclohexanonepyrazolones through a Cascade [4+2] Double Michael Addition
作者:Jin-Xin Zhang、Nai-Kai Li、Zhao-Min Liu、Xiao-Fei Huang、Zhi-Cong Geng、Xing-Wang Wang
DOI:10.1002/adsc.201200925
日期:2013.3.11
ortho‐fluorobenzoic acid is an efficient catalyst system for the doubleMichaeladdition of arylidenepyrazolones with α,β‐unsaturated ketones, providing chiral unsymmetrical 6,10‐diaryl‐substituted spiro[cyclohexanone‐pyrazolone] derivatives in high yields (up to 98%) with good diastereoselectivities and excellent enantioselectivities (up to 88:12 dr, 99% ee).
Organocatalytic 1,3-dipolar cycloaddition reaction of α,β-unsaturated ketones with azides through iminium catalysis
作者:Wenjun Li、Zhiyun Du、Kun Zhang、Jian Wang
DOI:10.1039/c4gc01929f
日期:——
1,3-Dipolarcycloadditionreaction of α,β-unsaturated ketones with azides through iminium catalysis has been developed. This method could furnish 1,4,5-trisubstituted 1,2,3-triazoles in good yields and high levels of regioselectivity.
We report a two-step synthesis of polysubstituted fluorenones by condensation of malononitrile with aromaticaldehydes and methylketones or with β-aryl-α,β-unsaturated carbonyl compounds, aldehydes or ketones. The yields of the fluorenone systems depend on the nature of the substitution on the aromatic rings.
Chiral Counteranion Synergistic Organocatalysis under High Temperature: Efficient Construction of Optically Pure Spiro[cyclohexanone-oxindole] Backbone
作者:Yu-Bao Lan、Hua Zhao、Zhao-Min Liu、Guo-Gui Liu、Jing-Chao Tao、Xing-Wang Wang
DOI:10.1021/ol201943g
日期:2011.9.16
The combination of a cinchona-based chiral primary amine and a BINOL-phosphoric acid has been demonstrated as a powerful and synergistic catalystsystem for the double Michaeladdition of isatylidene malononitriles with α,β-unsaturated ketones, to provide the novel chiral spiro [cyclohexane-1,3′-indoline]-2′,3-diones in high yields (88–99%) with excellent diastereo- and enantioselectivities (94:6–99:1
New benzoic acid derivatives, as well as processes for their production
申请人:Klinge Pharma GmbH
公开号:US04778925A1
公开(公告)日:1988-10-18
Para substituted benzoic acid derivatives of general formula (1) ##STR1## and their physiologically compatible salts, where R.sup.1 may be H, isopropyl, t-butyl p0 X may be ##STR2## and R.sup.2 may be --OH, --OR', where R' is a linear or branched, saturated or unsaturated C.sub.1 to C.sub.3 alkylmoiety, or a --NHCH.sub.2 COOH-- group, have hypolipedemic activity. They may be obtained by known methods either from the corresponding unsaturated ketones or from saturated hydroxycompounds, where the esterified benzoic acid moiety may be saponified or converted to a carboxymethylamide.