Reactions of 2,3-dihydrospiro[1<i>H</i>-4- and 5-azabenzimidazole-2,1′-cyclohexane] with nucleophiles: A potential route to some substituted aromatic heterocycles
results in loss of the Br-atom presumably by an AEa-mechanism. Reduction of the substituted azaisobenzimidazoles with sodium hydrosulfite followed by fission of the cyclohexane ring leads to substituted o-diaminopyridines. They were cyclised in situ with various condens ing agents to give new heterocyclic systems. Equimolar mixtures of some azaisobenzimidazoles and dihydroazabenzimidazoles lead to the
The effect of divergent-bite ligands on metal–metal bond distances in some paddlewheel complexes
作者:F.Albert Cotton、Lee M. Daniels、Carlos A. Murillo、Hong-Cai Zhou
DOI:10.1016/s0020-1693(99)00537-x
日期:2000.4
synthesized and crystallographically characterized. It has a CrCr distance of 2.016(1) Å, which is much longer than those in paddlewheel complexes with non-divergent dinitrogen ligands. This is the first example of a dichromium complex supported by a set of four divergent-bite ligands and no axial coordination. An analogous complex, namely Mo2(azin)4, where azin represents the anion of 7-azaindole
在桨轮型双金属单元中,桥联配体的最频繁排列具有这样的构型,使得两个供体轨道沿大致平行的线定向。但是,当配体具有两个衍生自六元环的供体原子之一,另一个衍生自稠合的五元环的另一个供体原子时,两个供体轨道将发散地定向。这种发散咬合的配体可能会延长MM键。由一组四个发散咬合配体Cr 2(CHIP)4支撑的CrCr核,其中CHIP是1',3'-二氢螺环[环己烷-1,2'-[2 H ]咪唑并[ 4,5 -b[吡啶],已经合成并在晶体学上进行了表征。CrCr距离为2.016(1)Å,比具有不扩散二氮配体的桨轮配合物长得多。这是由一组四个发散咬合的配体支持且没有轴向配位的重铬配合物的第一个例子。还已经描述了类似的络合物,即Mo 2(azin)4,其中azin代表7-氮杂吲哚的阴离子。与W 2(azin)4一起,据先前报道,已经获得了包裹在四个发散咬合配体的鞘中的第一批四重键。MM键的长度与具有更灵
Guanidine compound and heat sensitive recording material
申请人:FUJI PHOTO FILM CO., LTD.
公开号:US20020065194A1
公开(公告)日:2002-05-30
An object of the present invention is to provide a heat sensitive recording material which can develop color at high density by the inclusion of a novel guanidine compound which is strongly basic and superior in diffusion resistance. The present invention for attaining the above-described object is a heat sensitive recording material comprising a substrate supporting thereon a heat sensitive recording layer containing a diazonium salt compound, a coupler which reacts with the diazonium salt compound when heated to develop color, and a base, wherein the heat sensitive recording layer includes as the base at least one of the guanidine compounds represented by the general formula (1):
1
, wherein, in the general formula (1), R
1
and R
2
represent an alkyl group or aryl group and may be the same or different, R
3
and R
4
represent a hydrogen atom, alkyl group or halogen atom and may be the same or different, and X represents a divalent connecting group.
本发明的目的是提供一种热敏记录材料,通过加入一种新型胍化合物,该化合物具有强碱性和优越的抗扩散性,可在高密度下显色。为达到上述目的,本发明是一种热敏记录材料,它包括一个基片,基片上支撑着一个含有重氮盐化合物的热敏记录层,一个在加热时与重氮盐化合物反应而显色的耦合剂,以及一个碱基,其中热敏记录层包括至少一种由通式(1)表示的胍类化合物作为碱基:
1
其中,在通式(1)中,R
1
和 R
2
代表烷基或芳基,可以相同或不同,R
3
和 R
4
代表氢原子、烷基或卤素原子,可以相同或不同,X 代表二价连接基团。
A new route to 6-substituted 2,3-diaminopyridines
作者:Donald L. Bussolotti、John L. LaMattina、Keith James
DOI:10.1016/0040-4039(91)80204-j
日期:1991.11
2,3-Diaminopyridine reacts with cyclohexanone to form dihydro-4-azabenzimidazole-2-spirocyclohexane. Reaction of this intermediate with a variety of nucleophiles (e.g., water, phenylmercaptan, ethanol, dimethylamine, and diethylmalonate) in the presence of MnO2 results in addition to the 5-position. Subsequent acidic hydrogenation affords 6-substituted-2,3-diaminopyridines, key synthons for the synthesis of bicyclic heterocycles.
Dubey, Pramod Kumar; Ratnam, C. V., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1980, vol. 19, # 10, p. 863 - 865