Novel fluoro-substituted benzo- and benzothieno fused pyrano[2,3-c]pyrazol-4(1H)-ones
作者:Wolfgang Holzer、Angelika Ebner、Karin Schalle、Gyselle Batezila、Gernot A. Eller
DOI:10.1016/j.jfluchem.2010.07.007
日期:2010.10
A straightforward, two-step synthesis of fluoro substituted chromeno[2,3-c]pyrazol- and [1]benzothieno[2′,3′:5,6]pyrano[2,3-c]pyrazol-4(1H)-ones, respectively, is presented. Hence, treatment of 1-substituted or 1,3-disubstituted 2-pyrazolin-5-ones with fluoro substituted 2-fluorobenzoyl chlorides or 3-chloro-6-fluoro-1-benzothiophene-2-carbonyl chloride using calcium hydroxide in refluxing 1,4-dioxane
氟取代铬诺[2,3- c ]吡唑-和[1]苯并噻吩诺[2',3':5,6]吡喃[2,3 - c ]吡唑-4(1 H)的简单,两步合成)-一个,分别。因此,在回流条件下,使用氢氧化钙1用氟取代的2-氟苯甲酰氯或3-氯-6-氟-1-苯并噻吩-2-羰基氯处理1-取代或1,3-二取代的2-吡唑啉-5-酮。 ,4-二恶烷得到相应的4-芳酰基吡唑-5-醇,将其环化成稠环系统。通过用三氟乙酸处理1-(4-甲氧基苄基)保护的同类物,获得了5-氟铬诺[2,3- c ]吡唑-4(1 H)-。5-氟铬诺[2,3 - c ]吡唑-4(1)的处理用甲基肼得到的H)-酮提供了新颖的四环体系,例如2-甲基-7-苯基-2,7-二氢吡唑并[4',3':5,6]吡喃并[4,3,2- cd ]吲唑。对获得的化合物进行了详细的NMR光谱研究(1 H,13 C,15 N,19 F)。
An Efficient Approach to Heterocyclic Analogues of Xanthone: A Short Synthesis of All Possible Pyrido[5,6]pyrano[2,3-<i>c</i>]pyrazol-4(1<i>H</i>)-ones
An efficient and generally applicable synthesis of various [5,6]pyrano[2,3-c]pyrazol-4(1H)-ones by the reaction of either 1-substituted or 1,3-disubstituted 2-pyrazolin-5-ones with different o-halopyridinecarbonyl chlorides or with 3-chloroquinoline-2-carbonyl chloride, using calcium hydroxide in 1,4-dioxane, is described. In the course of the preparation of pyrazolo[4′,3′:5,6]pyrano[2,3-c]pyridin-4(1H)-ones, the intermediate 4-(3-chloroisonicotinoyl)-1H-pyrazol-5-ols did not cyclize spontaneously and thus were transformed into the corresponding tricycles by treatment with NaH in DMF. The N1-unsubstituted title compounds were obtained upon treatment of the corresponding 1-(4-methoxybenzyl) protected congeners with trifluoroacetic acid.
The synthesis of the title compounds is described. Reaction of 1-substituted 2-pyrazolin-5-ones with 5-chloro-1-phenyl-1H-pyrazole-4-carbonyl chloride or 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbonyl chloride, respectively, using calcium hydroxide in refluxing 1,4-dioxane gave the corresponding 4-heteroaroylpyrazol-5-ols, which were cyclized into 1H-pyrano[2,3-c:6,5-c]dipyrazol-4(7H)-ones by treatment
Pyrazolo[4′,3′:5,6]pyrano[2,3-<i>b</i>]quinoxalin-4(1<i>H</i>)-one: Synthesis and characterization of a novel tetracyclic ring system
作者:Gernot A. Eller、Barbara Datterl、Wolfgang Holzer
DOI:10.1002/jhet.5570440526
日期:2007.9
Derivatives of the hitherto unknown ringsystem, pyrazolo[4′,3′:5,6]pyrano[2,3-b]quinoxalin-4(1H)-one, are synthesized in one step from the corresponding 1-substuituted or 1,3-disubstituted 2-pyrazolin-5-ones and 3-chloroquinoxaline-2-carbonyl chloride using calcium hydroxide in boiling 1,4-dioxane. The parent system carrying no substituent in positions 1 and 3 is obtained upon treatment of the 1-PMB
迄今未知的环系统的衍生物吡唑并[4',3':5,6]吡喃并[2,3 - b ]喹喔啉-4(1 H)-一是从相应的1-取代基或-取代基合成的。在沸腾的1,4-二恶烷中使用氢氧化钙制备1,3-二取代的2-吡唑啉-5-酮和3-氯喹喔啉-2-羰基氯。通过用三氟乙酸处理1-PMB(对甲氧基苄基)保护的同类物,获得在位置1和3上不具有取代基的母体系统。报告了详细的NMR光谱研究,包括获得的四环的所有1 H,13 C和15 N共振的明确化学位移分配。
A Simple Synthesis of 6-Phenylpyrano[2,3-<i>c</i>]pyrazol-4(1<i>H</i>)-ones
作者:Wolfgang Holzer、Wilfried Becker、Gernot Eller
DOI:10.1055/s-2005-872078
日期:——
A novel synthesis of substituted 6-phenylpyrano[2,3-c]pyrazol-4(1H)-ones via reaction of various 2-substituted or 2,5-disubstituted 2,4-dihydro-3H-pyrazol-3-ones with phenylpropynoyl chloride using calcium hydroxide in refluxing 1,4-dioxane is described. N-Unsubstituted representatives were obtained by treatment of 4-methoxybenzyl-protected congeners with trifluoroacetic acid.