Hydrogen-bond-assisted transition-metal-free catalytic transformation of amides to esters
作者:Changyu Huang、Jinpeng Li、Jiaquan Wang、Qingshu Zheng、Zhenhua Li、Tao Tu
DOI:10.1007/s11426-020-9883-3
日期:2021.1
interest in synthetic chemistry, biological process and pharmaceutical industry. Transition-metal, luxury ligand or excess base were always vital to the transformation. Here, we developed a transition-metal-free hydrogen-bond-assisted esterification of amides with only catalytic amount of base. The proposed crucial role of hydrogen bonding for assisting esterification was supported by control experiments
Post‐Functionalization of an Anderson‐Type Polyoxomolybdate Using a Metal‐Free Diels–Alder Click Reaction
作者:Hai‐Kuan Yang、Ming‐Ming Su、Li‐Jun Ren、Jing Tang、Yu‐Kun Yan、Wen‐Ke Miao、Ping Zheng、Wei Wang
DOI:10.1002/ejic.201201399
日期:2013.3.11
properties. Accordingly, a major challenge lies in the development of efficient conjugation methods. In this work, we report our application of metal-free Diels–Alderclickreactions under mild conditions to covalently link an Anderson-type polyoxomolybdate with some organic groups or biological moieties possessing complex structures or different properties. High coupling efficiencies and facile purification
Photopolymerization initiator and photopolymerizable composition
申请人:Tokuyama Corporation
公开号:EP1431315A2
公开(公告)日:2004-06-23
A photopolymerization initiator comprising (A) a photo acid-generating compound such as diaryliodonium salt (e.g., diphenyl iodonium, bis(p-chlorophenyl)iodonium, etc.,), (B) a photo oxidation radical-generating compound such as diarylketone compound, α-diketone compound or ketocoumarin compound, and (C) a fused polycyclic aromatic compound such as 1,4-dimethylnaphthalene, 1-methylanthracene, 9-methylanthracene, 9,10-dimethylanthracene or 9,10-diethylanthracene. The photopolymerization initiator makes it possible to efficiently polymerize the cationically polymerizable monomer by the irradiation with visible light.
A cationically curable composition for dental use containing a cationic polymerization initiator (I) and cationically polymerizable monomers (II), the cationically polymerizable monomers (II) containing an oxetane compound and an epoxy compound or an alkenyl ether compound at a ratio of amounts that satisfy the conditions expressed by the following formula,
(a x A) : (b x B) = 91 : 9 to 45 : 55
wherein A is a mol number of the oxetane compound, "a" is an average number of the oxetane functional group contained in one molecule of the oxetane compound, B is a mol number of the epoxy compound or the alkenyl ether compound, and "b" is an average number of the epoxy functional group contained in one molecule of the epoxy compound or an average number of the alkenyl ether functional group contained in one molecule of the alkenyl ether compound.
The composition is not hindered by oxygen from being polymerized, cures quickly even without using a special polymerizable monomer or a particular polymerization initiator, little forms an unpolymerized layer on the surface even when polymerized and cured in a highly humid environment such as in the oral cavity, and is suited as a filling/restorative material for dental use.
一种用于牙科的阳离子固化组合物,含有阳离子聚合引发剂(I)和阳离子可聚合单体(II),阳离子可聚合单体(II)含有氧杂环丁烷化合物和环氧化合物或烯基醚化合物,其用量比例满足下式所表示的条件、
(a x A) : (b x B) = 91 : 9 至 45 :55
其中 A 是氧杂环丁烷化合物的摩尔数,"a "是一分子氧杂环丁烷化合物中所含的氧杂环丁烷官能团的平均数,B 是环氧化合物或烯基醚化合物的摩尔数,"b "是一分子环氧化合物中所含的环氧官能团的平均数或一分子烯基醚化合物中所含的烯基醚官能团的平均数。
该组合物的聚合不受氧气阻碍,即使不使用特殊的可聚合单体或特定的聚合引发剂也能快速固化,即使在口腔等高湿度环境中聚合固化,也几乎不会在表面上形成未聚合层,适合作为牙科用填充/修复材料。
METHOD FOR PRODUCING PLATE DENTURE, CURABLE STEREOLITHOGRAPHIC COMPOSITION, AND PLATE DENTURE PRODUCTION KIT
申请人:Tokuyama Dental Corporation
公开号:EP4091578A1
公开(公告)日:2022-11-23
[Object] To provide a method of producing a plate denture using a stereolithography 3D printer, which is capable of producing a plate denture in a short time with a more simplified production process, the plate denture exhibiting excellent occlusion.
[Solving Means] The problem is solved by a method of producing a plate denture, including: adhering an artificial tooth and a denture base photochemically solidified by a stereolithography 3D printer to each other by polymerizing an unpolymerized curable composition for stereolithography present on a surface of the denture base. Further, stronger adhesion between the artificial tooth and the denture base is achieved by mixing, in the curable composition for stereolithography, a polymerization initiator other than a photopolymerization initiator for stereolithography.