A novel surface active monomer （surfmer） containing poly（ethylene glycol） chain and terminated phosphate group was synthesized. The copolymerization of synthesized surfmer with NVP （N-vinylpyrrolidone） and with ...A novel surface active monomer （surfmer） containing poly（ethylene glycol） chain and terminated phosphate group was synthesized. The copolymerization of synthesized surfmer with NVP （N-vinylpyrrolidone） and with NVP and VEP （5-tert-butylperoxy-5-methyl-2-hexene-3-yne monomer） led to formation of corresponding surface-active copolymers. The capability of application of resulted copolymers as surface active macroinitiators of emulsion polymerization of styrene and as components of polymeric scaffolds was investigated.展开更多
A series of 4,4＇-disubstituted-[2,2＇]-bipyridines, featuring electron withdrawing/donating functional groups such as amino, chloro, nitro, ethoxycarbonyl, carboxy, methyl, methoxy and hydroxymethyl, have been syn- t...A series of 4,4＇-disubstituted-[2,2＇]-bipyridines, featuring electron withdrawing/donating functional groups such as amino, chloro, nitro, ethoxycarbonyl, carboxy, methyl, methoxy and hydroxymethyl, have been syn- thesized and employed in the copolymerization of carbon monoxide （CO） and styrene. The available bipyridine and its derivatives were coordinated with palladium （ II ） acetate for catalyzing the copolymerization of CO and styrene, and the concomitant polyketone was characterized by means of t3C NMR, FTIR, differential scanning calo- rimetry （DSC） and element analysis techniques concerning its structure and thermal performance. The effect of dif- ferent electron-donating and electron-withdrawing groups on catalyst performance and molecular weight of co- polymer was studied under certain experimental condition. It has been proved that the enhancement of electron donating and conjugative effects on bipyridine ligand will not only improve the catalytic activity of the composi- tion, but also increase the molecular weight of the as-prepared polyketone. The catalytic activity is the highest in hydroxymethyl substituted 2,2＇-bipyridine ligand（l 356 gSTCO/（gPd · h））, when the molecular weight and polydispersity index of the polyketone are Mn = 8 502, Mw = 1 3440 and Mw/Mn = 1.581, respectively.展开更多
Transition-metal-catalyzed C–H bond activation represents one of the most attractive research areas in organic synthesis.In contrast to the great developments made in directed C–H bond functionalization of arenes,th...Transition-metal-catalyzed C–H bond activation represents one of the most attractive research areas in organic synthesis.In contrast to the great developments made in directed C–H bond functionalization of arenes,the directing group-assisted activation of non-aromatic vinylic C–H bonds still remains challenging.During the recent years,significant progress has been made in this fascinating field with various functionalized alkenes,heterocycles and carbocycles being obtained.This article will focus on the recent achievements in the field of directing-group-assisted vinylic C–H bond functionalization.展开更多
Based on isolobal analogy,the definition of metallafuran was described and its synthetic chemistry was briefly summarized.In the structure of furan,when one of CH groups was replaced by an isolobal metal fragment ML n...Based on isolobal analogy,the definition of metallafuran was described and its synthetic chemistry was briefly summarized.In the structure of furan,when one of CH groups was replaced by an isolobal metal fragment ML n(M=metal;L=ligand),the corresponding organometallic complex was called metallafuran,which should be two possible isomers called a-metallafuran(metal fragment at a-carbon of original furan)and b-metallafuran(metal fragment at b-carbon of original furan).As an organometallic complex,a-metallafuran has two resonant forms:one can be viewed as carbonyl coordinated vinyl metal complex and the other can be viewed as alkoxymetal carbene.Therefore,a-metallafuran was also called chelated vinyl ketone metal complex or oxametallacyclopentadiene in the early literatures.For synthesis of metallafurans,a-metallafurans were very common and easily prepared,for example,from alkynes insertion into acyl metal complexes and so on.While there were rare examples reported for b-metallafurans.In this mini review,the synthetic chemistry of metallafuran was mainly focused on its formation mechanism.展开更多
文摘A novel surface active monomer （surfmer） containing poly（ethylene glycol） chain and terminated phosphate group was synthesized. The copolymerization of synthesized surfmer with NVP （N-vinylpyrrolidone） and with NVP and VEP （5-tert-butylperoxy-5-methyl-2-hexene-3-yne monomer） led to formation of corresponding surface-active copolymers. The capability of application of resulted copolymers as surface active macroinitiators of emulsion polymerization of styrene and as components of polymeric scaffolds was investigated.
基金Supported by Tianjin Natural Science Foundation(No.07JCYBJC00600)
文摘A series of 4,4＇-disubstituted-[2,2＇]-bipyridines, featuring electron withdrawing/donating functional groups such as amino, chloro, nitro, ethoxycarbonyl, carboxy, methyl, methoxy and hydroxymethyl, have been syn- thesized and employed in the copolymerization of carbon monoxide （CO） and styrene. The available bipyridine and its derivatives were coordinated with palladium （ II ） acetate for catalyzing the copolymerization of CO and styrene, and the concomitant polyketone was characterized by means of t3C NMR, FTIR, differential scanning calo- rimetry （DSC） and element analysis techniques concerning its structure and thermal performance. The effect of dif- ferent electron-donating and electron-withdrawing groups on catalyst performance and molecular weight of co- polymer was studied under certain experimental condition. It has been proved that the enhancement of electron donating and conjugative effects on bipyridine ligand will not only improve the catalytic activity of the composi- tion, but also increase the molecular weight of the as-prepared polyketone. The catalytic activity is the highest in hydroxymethyl substituted 2,2＇-bipyridine ligand（l 356 gSTCO/（gPd · h））, when the molecular weight and polydispersity index of the polyketone are Mn = 8 502, Mw = 1 3440 and Mw/Mn = 1.581, respectively.
基金supported by the National Basic Research Program of China(2015CB856600)the National Natural Science Foundation of China(21332002,21272010)
文摘Transition-metal-catalyzed C–H bond activation represents one of the most attractive research areas in organic synthesis.In contrast to the great developments made in directed C–H bond functionalization of arenes,the directing group-assisted activation of non-aromatic vinylic C–H bonds still remains challenging.During the recent years,significant progress has been made in this fascinating field with various functionalized alkenes,heterocycles and carbocycles being obtained.This article will focus on the recent achievements in the field of directing-group-assisted vinylic C–H bond functionalization.
基金supported by the National Natural Science Foundation of China (21302158 and 21472156)the National Basic Research Program of China (2012CB821600)
文摘Based on isolobal analogy,the definition of metallafuran was described and its synthetic chemistry was briefly summarized.In the structure of furan,when one of CH groups was replaced by an isolobal metal fragment ML n(M=metal;L=ligand),the corresponding organometallic complex was called metallafuran,which should be two possible isomers called a-metallafuran(metal fragment at a-carbon of original furan)and b-metallafuran(metal fragment at b-carbon of original furan).As an organometallic complex,a-metallafuran has two resonant forms:one can be viewed as carbonyl coordinated vinyl metal complex and the other can be viewed as alkoxymetal carbene.Therefore,a-metallafuran was also called chelated vinyl ketone metal complex or oxametallacyclopentadiene in the early literatures.For synthesis of metallafurans,a-metallafurans were very common and easily prepared,for example,from alkynes insertion into acyl metal complexes and so on.While there were rare examples reported for b-metallafurans.In this mini review,the synthetic chemistry of metallafuran was mainly focused on its formation mechanism.
