Dendrimers are perfect monodisperse macromolecules with a regular and highly branched three-dimensional architecture, so their unique physical and chemical properties are noticed and utilized more and more.[1] The... Dendrimers are perfect monodisperse macromolecules with a regular and highly branched three-dimensional architecture, so their unique physical and chemical properties are noticed and utilized more and more.[1] The dendrimer architecture can offer a means of better controlling the disposition of the catalytic species in soluble polymer-based catalysts and such novel catalysts of nano-scale size may aid the recycling of catalysts simply by supra-filtration or solvent precipitation methods.……展开更多
The reduction of C = C double bonds is one of the most fundamental synthetic transformations and plays a key role in the manufacturing of a wide variety of bulk and fine chemicals. Hydrogenation of olefinic substr... The reduction of C = C double bonds is one of the most fundamental synthetic transformations and plays a key role in the manufacturing of a wide variety of bulk and fine chemicals. Hydrogenation of olefinic substrates can be achieved readily with molecular hydrogen in many cases, but transfer hydrogenation methods using suitable donor molecules such as formic acid or alcohols are receiving increasing attention as possible synthetic alternatives because it requires no special equipment and avoids the handling of potentially hazardous gaseous hydrogen.……展开更多
Carboxylic acids are important in crystal engineering because they can form strong and directional O-H…O hydrogen bonds as dimmer and catmer.[1] The dicarboxylic acids (not containing other hydrogen bonding group... Carboxylic acids are important in crystal engineering because they can form strong and directional O-H…O hydrogen bonds as dimmer and catmer.[1] The dicarboxylic acids (not containing other hydrogen bonding groups) generally form the extended line structure interlinked through dimmer,[2] except that oxalic acid forms both the β-oxalic acid linked by dimmer (finite synthon) and the a-oxalic acid by catmer[3] (infinite synthon). A new molecular packing structure of cis-1,3-cyclohexanedicarboxylic acid (CHDA), which is different from line structure,[4] was gotten (P1/2, Figure 1). The novel structure has dimmer and catmer hydrogen bond pairs in the crystal and the hydrogen bond length of O-H…O is 0.268 nm in catmer and 0.264 nm in dimmer. The bond angles of O=C-O vary from 123.1° to 123.8° in catmer and from 123.1° to 122.0° in dimmer comparing with the ones in line structure.……展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 203900507, 20025205).
文摘 Dendrimers are perfect monodisperse macromolecules with a regular and highly branched three-dimensional architecture, so their unique physical and chemical properties are noticed and utilized more and more.[1] The dendrimer architecture can offer a means of better controlling the disposition of the catalytic species in soluble polymer-based catalysts and such novel catalysts of nano-scale size may aid the recycling of catalysts simply by supra-filtration or solvent precipitation methods.……
基金Project supported by the National Natural Science Foundation of China (Nos. 203900507, 20025205).
文摘 The reduction of C = C double bonds is one of the most fundamental synthetic transformations and plays a key role in the manufacturing of a wide variety of bulk and fine chemicals. Hydrogenation of olefinic substrates can be achieved readily with molecular hydrogen in many cases, but transfer hydrogenation methods using suitable donor molecules such as formic acid or alcohols are receiving increasing attention as possible synthetic alternatives because it requires no special equipment and avoids the handling of potentially hazardous gaseous hydrogen.……
基金Project suppored by the National Natural Science Foundation of China (Nos. 20172052, 20025205).
文摘 Carboxylic acids are important in crystal engineering because they can form strong and directional O-H…O hydrogen bonds as dimmer and catmer.[1] The dicarboxylic acids (not containing other hydrogen bonding groups) generally form the extended line structure interlinked through dimmer,[2] except that oxalic acid forms both the β-oxalic acid linked by dimmer (finite synthon) and the a-oxalic acid by catmer[3] (infinite synthon). A new molecular packing structure of cis-1,3-cyclohexanedicarboxylic acid (CHDA), which is different from line structure,[4] was gotten (P1/2, Figure 1). The novel structure has dimmer and catmer hydrogen bond pairs in the crystal and the hydrogen bond length of O-H…O is 0.268 nm in catmer and 0.264 nm in dimmer. The bond angles of O=C-O vary from 123.1° to 123.8° in catmer and from 123.1° to 122.0° in dimmer comparing with the ones in line structure.……
