Catalytic Syntheses of N-Heterocyclic Ynones and Ynediones by In Situ Activation of Carboxylic Acids with Oxalyl Chloride
作者:Christina Boersch、Eugen Merkul、Thomas J. J. Müller
DOI:10.1002/anie.201103296
日期:2011.10.24
bottleneck: α‐Keto carboxylicacids and N‐heterocyclic carboxylicacids are activated in situ with oxalylchloride then catalytically alkynylated to give ynediones and N‐heterocyclic ynones efficiently in a one‐pot fashion. 5‐Acylpyrazoles and 2‐phenylaminopyrimidines, potentially interesting for pharmaceutical applications, are readily synthesized in concise one‐pot, three‐component syntheses.
Pyridazine <i>N</i>-Oxides as Photoactivatable Surrogates for Reactive Oxygen Species
作者:Vitalii S. Basistyi、James H. Frederich
DOI:10.1021/acs.orglett.2c00227
日期:2022.3.18
evolution of atomic oxygen from pyridazineN-oxides was developed. This underexplored oxygen allotrope mediates arene C–H oxidation within complex, polyfunctional molecules. A water-soluble pyridazineN-oxide was also developed and shown to promote photoinduced DNA cleavage in aqueous solution. Taken together, these studies highlight the utility of pyridazineN-oxides as photoactivatable O(3P) precursors
开发了一种从哒嗪N-氧化物光诱导析出原子氧的方法。这种尚未开发的氧同素异形体介导复杂的多功能分子内的芳烃 C-H 氧化。还开发了一种水溶性哒嗪N-氧化物,并显示其可促进水溶液中的光诱导 DNA 裂解。总而言之,这些研究强调了哒嗪N-氧化物作为可光活化的 O( 3 P) 前体在有机合成和化学生物学中的应用。
Unexpected pyrazolo[4,3-d][2,3]benzodiazepine synthesis from 1-(N,N-diaroyl)amino-4-phenyl-[1,2,3]triazol-5-yl-methyltriphenylphosphonium bromide via tandem phosphorylide formation and subsequent Dimroth-like rearrangement of the triazole ring
作者:Efstathios Laskos、Pygmalion S. Lianis、Nestor A. Rodios、A. Terzis、C.P. Raptopoulou
DOI:10.1016/0040-4039(95)01034-f
日期:1995.7
giving the very stable phosphorus ylide 5. Refluxing of 5 in xylene gave the unexpected 3-aroyl-6-arylpyrazolo[4,3-d][2,3]benzodiazepines6 by a Dimroth-like rearrangement of the triazole ring and a 1,7-electrocyclization of the nitrilimine intermediate 11. When the xylene solution was not rigorously refluxed the 3(5)-aroyl-5(3)-phenyl pyrazole 7 was isolated. The x-raycrystalstructures of compounds
1-(N,N-二芳酰基)氨基-4-苯基-1,2,3-三唑-5-基-甲基三苯基溴化phosph 2与叔丁醇钾或三乙胺在干燥的甲苯中反应,得到非常稳定的磷内鎓盐5。5在二甲苯中的回流通过三唑环的类似Dimroth的重排和腈腈胺中间体的1,7-电环化作用产生了意外的3-芳酰基-6-芳基吡唑并[4,3- d ] [2,3]苯并二氮杂卓6 11。当不严格回流二甲苯溶液时,分离出3(5)-芳酰基-5(3)-苯基吡唑7。还给出了化合物5d和6b的X射线晶体结构。
Denitrogenative dismantling of heteroaromatics by nucleophilic substitution reactions with diazomethyl compounds
作者:Soumen Biswas、Claire Empel、Luis Mario Sanchez-Palestino、Hadi Arman、Rene M. Koenigs、Michael P. Doyle
DOI:10.1039/d4sc01578a
日期:——
Nucleophiles from deprotonation of diazomethyl compounds having diverse electron withdrawing groups react with 4-carboxylato-1,2,3-triazines at the 6-position to extrude dinitrogen and produce diazovinylketoesters compounds with five or six linear contiguous sp2-hybridized carbons, whereas these same nucleophiles react with 4-carboxylato-1,2,3-triazine 1-oxides, also at the 6-position, to form pyrazolines
An unexpected C-C bond cleavage has been revealed in the absence of metal. This observation has been exploited to develop an efficient approach toward 3,6-iarylpyridazines and 6-arylpyridazin-3-ones from simple and commercially available 1,3-dicarbonyl compounds and methyl ketones.