- Structure-dependent regioselectivity of a roll-over cyclopalladation occuring at 2,2′-bipyridine-type ligands
-
In this work, different bipyridine-analogue ligands bearing a dimethylamino group in the meta-position of one of the heterocyclic rings were synthesized and reacted with palladium(II) acetate under identical conditions. Cyclometallated palladium(II) complexes with C,N- or C,N,N’-coordinating chelate ligands are formed which were characterized by elemental analysis, 1H and 13C NMR spectroscopy, and single crystal X-ray diffraction analysis. In the case of the mononuclear, C,N,N’-coordinated complex, which is formed by an attack of the palladium(II) site at of the N-methyl groups, the primarily coordinating acetato ligand is exchanged against a chlorido ligand, which is liberated from the solvent dichloromethane by a nucleophilic substitution reaction. In contrast, cyclometallation occurring at one of the six-membered heterocycles leads to dinuclear acetato-bridged palladium(II) complexes.
- Becker, Yanik,Sch?n, Florian,Becker, Sabine,Sun, Yu,Thiel, Werner R.
-
-
- A gas-phase study on the cyclometallation of a series of Cp*Ir(III) complexes bearing bidentate pyrimidine ligands
-
A concerted approach of synthesis and gas phase experiments characterizes the relative cyclometallation barriers of a series of cationic η5-Cp* iridium(III) compounds. The common feature of the investigated compounds is a bidentate N,N’-donor ligand possessing a pyridine site functionalized with a 5-butylpyrimidin-2-yl ring in the 2-position. In addition, the pyridine ring was functionalized with electron-donating or -withdrawing groups. The compounds were characterized by means of NMR and IR spectroscopy and elemental analysis. For the measurements of the relative barriers of the cyclometallation, collision-induced dissociation (CID) experiments were carried out, which revealed a clear dependence of the relative barriers from the nature and the position of the substituents at the pyridine ring could be worked out.
- Becker, Sabine,Becker, Yanik,Huber, Maximilian,Niedner-Schatteburg, Gereon,Sun, Yu,Thiel, Werner R.
-
-
- Preparation method of 2, 3-dichloro-6-cyanopyridine
-
The invention discloses a preparation method of 2, 3-dichloro-6-cyanopyridine, and the method comprises the following steps: by using a metal chloride salt as a catalyst and phosphorus halide as a cocatalyst, carrying out one-step liquid-phase chlorination reaction on raw materials 2-chloro-6-cyanopyridine and chlorine to obtain 2, 3-dichloro-6-cyanopyridine; wherein the metal chloride salt is selected from at least one of WCl6, MoCl5, FeCl3, AlCl3, CuCl2, ZnCl2, RuCl3, SnCl4 and SbCl5, and the cocatalyst is selected from at least one of phosphorus pentachloride, phosphorus trichloride, phosphorus pentabromide and phosphorus tribromide. The method is simple in reaction process, low in production cost and high in target product selectivity and yield, the yield is 90% or above by optimizingreaction conditions, and the method has a good industrial prospect.
- -
-
Paragraph 0020
(2020/05/08)
-
- Synthesis and structure-activity relationships of amide derivatives of (4,4-difluoro-1,2,3,4-tetrahydro-5H-1-benzazepin-5-ylidene)acetic acid as selective arginine vasopressin V2 receptor agonists
-
A series of (4,4-difluoro-1,2,3,4-tetrahydro-5H-1-benzazepin-5-ylidene)acetamide derivatives was synthesized, and their structure-activity relationships were examined in order to identify potent and selective arginine vasopressin V2 receptor agonists. Attempts to substitute other chemical groups in place of the 2-pyridilmethyl moiety of 1a led to the discovery that potent V2 binding affinity could be obtained with a wide range of functional groups. This structural tolerance allowed for the manipulation of other attributes, such as selectivity against V1a receptor affinity or avoidance of the undesirable inhibition of cytochrome P450 (CYP), without losing potent affinity for the V2 receptor. Some representative compounds obtained in this study were also found to decrease urine volume in awake rats.
- Tsukamoto, Issei,Koshio, Hiroyuki,Kuramochi, Takahiro,Saitoh, Chikashi,Yanai-Inamura, Hiroko,Kitada-Nozawa, Chika,Yamamoto, Eisaku,Yatsu, Takeyuki,Shimada, Yoshiaki,Sakamoto, Shuichi,Tsukamoto, Shin-ichi
-
experimental part
p. 3130 - 3141
(2009/09/30)
-
- 1,3-BENZOTHIAZINONE DERIVATIVES AND USE THEREOF
-
This invention provides a compound represented by the formula (I) :wherein R1 is a hydrogen atom, a halogen atom, hydroxy, nitro, optionally halogenated alkyl, alkoxy optionally having substituents, acyl or amino optionally having substituents;R2 is pyridyl, furyl, thienyl, pyrrolyl, quinolyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolyl, tetrahydroquinolyl or thiazolyl, each of which may have substituents;n is 1 or 2; or a salt. And this invention provides a safe pharmaceutical comprising the compound of the formula (I) , which has an excellent apoptosis inhibitory effect and MIF binding effect, for preventing and/or treating heart disease, nervous degenerative disease, cerebrovascular disease, central nervous infectious disease, traumatorathy, demyelinating disease, bone and articular disease, kidney disease, liver disease, osteomyelodysplasia, AIDS, cancer, and the like.
- -
-
-
- Preparation of substituted 2-chloropyridines
-
A process for the preparation of a substituted 2-chloropyridine derivatives of the formula STR1 in which R1, R2, R3 and R4 represent hydrogen or various other radicals, which comprises reacting a pyridine-1-oxide of the formula STR2 with an aromatic carbonyl chloride in the presence of an inert organic solvent and in the presence of an acid acceptor at a temperature between about -20° C. and 200° C.
- -
-
-
- Process for the preparation of substituted 2-chloropyridines
-
A new process has been found for the preparation of substituted 2-chloropyridine derivatives of the formula (I) STR1 wherein R1 to R4 have the meanings as defined in the description. The new process is characterized in that pyridine 1-oxides of the formula II STR2 are reacted with a chlorine-containing phosphoric acid derivative from the series of the chlorophosphoric esters and chlorophosphoramides in the presence of an inert organic solvent and in the presence of an acid acceptor at temperatures between -20° C. and 200° C., and the resulting product is separated further, if appropriate. Compound (I) is known as an intermediate product for medicaments (cf.DE-A 2,812,585) or for insecticidel nitromethylene derivatives (cf. EP-A 163,855).
- -
-
-
- SOLVENT AND TEMPERATURE DEPENDENT REGIOSELECTIVE REACTIONS BETWEEN 2-CHLORO-6-CYANOPYRIDINE AND ALIPHATIC ALCOHOLS
-
Reaction of 2-chloro-6-cyanopyridine with aliphatic mono- and di-alcohols or ethylene glycols affords, depending on the reaction conditions, alkoxypyridines or imino ester pyridines or a mixture of both types of compounds.It is suggested that the product distribution is determined by the stability of an imidate anion formed as an intermediate.An improved synthesis of 2-chloro-6-cyanopyridine is also described.
- Elman, Bjoern
-
p. 4941 - 4948
(2007/10/02)
-
- Site-Selectivity in the Cyanation of 3-Substituted Pyridine 1-Oxides with Trimethylsilanecarbonitrile
-
The cyanation of 3-halo-, 3-methoxy-, and 3-dimethylaminopyridine 1-oxide with trimethylsilanecarbonitrile gave predominantly the corresponding 3-substituted 2-pyridinecarbonitriles.The deoxygenation of nitropyridine 1-oxides to nitropyridines with the same reagent is also described.Keywords - site-selective reaction; trimethylsilanecarbonitrile; pyridine 1-oxide; 2-pyridine-carbonitrile; nitropyridine 1-oxide; deoxygenation; aromatic amine N-oxide; cyanation
- Sakamoto, Takao,Kaneda, Soh-ichi,Nishimura, Sumiko,Yamanaka, Hiroshi
-
p. 565 - 571
(2007/10/02)
-
- ipso-Substitution of a Sulphinyl or Sulphonyl Group Attached to Pyridine Rings and its Application for the Synthesis of Macrocycles
-
A sulphinyl or sulphonyl group directly bound to the 2- or 4-position of a pyridine ring was readily displaced by several nucleophiles such as RO-, RS-, and CN- to afford the corresponding ipso-substitution products.Similarly, 2-halogeno-6-methylsulphinyl- or -methylsulphonyl-pyridines also react with nuclephiles to afford 2-halogeno-6-substituted pyridine derivatives.Thus, the leaving abilities of the leaving groups fall in the order RSO2 > RSO > Br ca.Cl >> RS (R = alkyl or benzyl).The ipso-substitution can be applied to the synthesis of 2,6-disubstituted pyridino macrocycles containing both carbon-oxygen and carbon-sulphur bridges, resulting in several new macrocycles in moderate yields.
- Furukawa, Naomichi,Ogawa, Satoshi,Kawai, Tsutomu,Oae, Shigeru
-
p. 1839 - 1845
(2007/10/02)
-