Various addition-elimination approaches have been explored for diastereoselective construction of 1-amino- 1-cyclopropane-carboxylic acid (ACPC) derivatives, and the desired product was obtained from a reaction of cyc...Various addition-elimination approaches have been explored for diastereoselective construction of 1-amino- 1-cyclopropane-carboxylic acid (ACPC) derivatives, and the desired product was obtained from a reaction of cyclo(NAc-L-Val-NAc-Gly) and methyl α-bro-moacrylate under protonic solvent.展开更多
3-(Dimethylamino)-1-phenylprop-2-en-1-ones (formylated acetophenones) 1 reacted with aliphatic diamines in water assisted by KHSO4 to give bis-enaminones 2a-h in good yields. Compound 1 also reacted with o-phenylenedi...3-(Dimethylamino)-1-phenylprop-2-en-1-ones (formylated acetophenones) 1 reacted with aliphatic diamines in water assisted by KHSO4 to give bis-enaminones 2a-h in good yields. Compound 1 also reacted with o-phenylenediamine under similar conditions to produce bis-enaminones 3 instead of benzodiazepines 4 in excellent yields.展开更多
The reaction of HFe<sub>2</sub>Co（CO）<sub>9</sub>（μ<sub>3</sub>-S）with（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>...The reaction of HFe<sub>2</sub>Co（CO）<sub>9</sub>（μ<sub>3</sub>-S）with（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）Mo（CO）<sub>3</sub>CI has been carried outin refluxing tetrahydrofuran（THF）to give out heterometallic trinuclear clusters（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）MoFeCo-（CO）<sub>8</sub>（μ<sub>3</sub>-S）and（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）<sub>2</sub>Mo<sub>2</sub>Fe（CO）<sub>7</sub>（μ<sub>3</sub>-S）by electrophilic addition-elimination reaction.Howev-er,（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）Fe（CO）<sub>2</sub>Cl reacted with HFe<sub>2</sub>Co（CO）<sub>9</sub>（μ<sub>3</sub>-S）at room temperature to yield a tetranuclearcluster（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）Fe<sub>3</sub>Co（CO）<sub>11</sub>（μ<sub>4</sub>-S）.The μ<sub>4</sub>-S cluster could be used as an intermediate in confirmationof the mechanism of the electrophilic addition-elimination reaction.The syntheses,characterizations andX-ray crystal structures of these clusters are reported herein as well as the discussion on the reaction mecha-nism.展开更多
Starting from（5S）-（L-menthyloxy）-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[（2S）-4-bromo-2-（L-menthyloxy）-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5（C20H32BrNO5,Mr = 446.37） was obtained in o...Starting from（5S）-（L-menthyloxy）-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[（2S）-4-bromo-2-（L-menthyloxy）-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5（C20H32BrNO5,Mr = 446.37） was obtained in one-pot process via the tandem Michael addition-elimination reaction in the presence of potassium hydroxide.The chemical structure and absolute configuration of the title compound were confirmed via rotation,UV-Vis,FT-IR,1H NMR,13C NMR,MS and elemental analysis,especially by the X-ray single-crystal diffraction.The crystal crystallizes in an orthorhombic system,space group P212121 with a = 12.5249（16）,b = 19.005（3）,c = 19.719（3） ,V = 4693.7（10） 3,Z = 8,Dc = 1.263 g/m3,μ = 1.778 mm-1,F（000） = 1872,the final R = 0.0617 and wR = 0.1576 for 3967 observed reflections（I 2σ（I））.X-ray analysis reveals that the title compound has two independent molecules in the asymmetric part of the unit cell with the two five-membered furanones being almost planar.The essential part of the electron delocalization is concentrated in the N（1）,C（3）,C（1）,C（37） and O（7） region and N（2）,C（28）,C（27）,C（30） and O（4） region in the other molecule respectively,but does not take place at the expense of delocalization within the ester function.展开更多
Phycobiliproteins, part of the photosynthetic apparatus in algae, are a group of important absorbers of light, in which the functional groups for light absorption are linear tetrapyrrole chromophores. In order to inte...Phycobiliproteins, part of the photosynthetic apparatus in algae, are a group of important absorbers of light, in which the functional groups for light absorption are linear tetrapyrrole chromophores. In order to interpret the photobiological phenomenon of the phycobiliproteins, it is important to investigate the chemical properties and the formation of the derivatives of the chromophores.展开更多
A novel method for the synthesis of 2-chloro enesulfonamides via the one-pot addition-elimination of N-chloro-N-fluorobenzenesulfonamides （CFBSA） to styrenes in the presence of Et3N is described. A total of 20 examp...A novel method for the synthesis of 2-chloro enesulfonamides via the one-pot addition-elimination of N-chloro-N-fluorobenzenesulfonamides （CFBSA） to styrenes in the presence of Et3N is described. A total of 20 examples are presented to illustrate this concept including various of styrenes.展开更多
In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of...In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5-(ι-menthyloxy)-4-substituted-3-cnloro-2(5H)-furanones, were obtained in good yields with d. e.(?)98% under mild conditions.展开更多
文摘Various addition-elimination approaches have been explored for diastereoselective construction of 1-amino- 1-cyclopropane-carboxylic acid (ACPC) derivatives, and the desired product was obtained from a reaction of cyclo(NAc-L-Val-NAc-Gly) and methyl α-bro-moacrylate under protonic solvent.
文摘3-(Dimethylamino)-1-phenylprop-2-en-1-ones (formylated acetophenones) 1 reacted with aliphatic diamines in water assisted by KHSO4 to give bis-enaminones 2a-h in good yields. Compound 1 also reacted with o-phenylenediamine under similar conditions to produce bis-enaminones 3 instead of benzodiazepines 4 in excellent yields.
文摘The reaction of HFe<sub>2</sub>Co（CO）<sub>9</sub>（μ<sub>3</sub>-S）with（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）Mo（CO）<sub>3</sub>CI has been carried outin refluxing tetrahydrofuran（THF）to give out heterometallic trinuclear clusters（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）MoFeCo-（CO）<sub>8</sub>（μ<sub>3</sub>-S）and（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）<sub>2</sub>Mo<sub>2</sub>Fe（CO）<sub>7</sub>（μ<sub>3</sub>-S）by electrophilic addition-elimination reaction.Howev-er,（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）Fe（CO）<sub>2</sub>Cl reacted with HFe<sub>2</sub>Co（CO）<sub>9</sub>（μ<sub>3</sub>-S）at room temperature to yield a tetranuclearcluster（η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>CH<sub>3</sub>）Fe<sub>3</sub>Co（CO）<sub>11</sub>（μ<sub>4</sub>-S）.The μ<sub>4</sub>-S cluster could be used as an intermediate in confirmationof the mechanism of the electrophilic addition-elimination reaction.The syntheses,characterizations andX-ray crystal structures of these clusters are reported herein as well as the discussion on the reaction mecha-nism.
基金Supported by the National Natural Science Foundation of China (No. 20772035)the Natural Science Foundation of Guangdong Province (No. 5300082)
文摘Starting from（5S）-（L-menthyloxy）-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[（2S）-4-bromo-2-（L-menthyloxy）-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5（C20H32BrNO5,Mr = 446.37） was obtained in one-pot process via the tandem Michael addition-elimination reaction in the presence of potassium hydroxide.The chemical structure and absolute configuration of the title compound were confirmed via rotation,UV-Vis,FT-IR,1H NMR,13C NMR,MS and elemental analysis,especially by the X-ray single-crystal diffraction.The crystal crystallizes in an orthorhombic system,space group P212121 with a = 12.5249（16）,b = 19.005（3）,c = 19.719（3） ,V = 4693.7（10） 3,Z = 8,Dc = 1.263 g/m3,μ = 1.778 mm-1,F（000） = 1872,the final R = 0.0617 and wR = 0.1576 for 3967 observed reflections（I 2σ（I））.X-ray analysis reveals that the title compound has two independent molecules in the asymmetric part of the unit cell with the two five-membered furanones being almost planar.The essential part of the electron delocalization is concentrated in the N（1）,C（3）,C（1）,C（37） and O（7） region and N（2）,C（28）,C（27）,C（30） and O（4） region in the other molecule respectively,but does not take place at the expense of delocalization within the ester function.
基金Project supported by the National Natural Science Foundation of China and the United Analytical Testing Center in Zhongguancun Area.
文摘Phycobiliproteins, part of the photosynthetic apparatus in algae, are a group of important absorbers of light, in which the functional groups for light absorption are linear tetrapyrrole chromophores. In order to interpret the photobiological phenomenon of the phycobiliproteins, it is important to investigate the chemical properties and the formation of the derivatives of the chromophores.
基金We are grateful to the National Natural Science Foundation of China （No. 21372077） for financial support. This work was supported by ＂the Fundamental Research Funds for the Central Universities （No. 222201717003）.
文摘A novel method for the synthesis of 2-chloro enesulfonamides via the one-pot addition-elimination of N-chloro-N-fluorobenzenesulfonamides （CFBSA） to styrenes in the presence of Et3N is described. A total of 20 examples are presented to illustrate this concept including various of styrenes.
基金Project (No. 29132036) supported by the National Natural Science Foundation of China
文摘In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5-(ι-menthyloxy)-4-substituted-3-cnloro-2(5H)-furanones, were obtained in good yields with d. e.(?)98% under mild conditions.
