932-97-8Relevant academic research and scientific papers
Chemoselective rearrangement reactions of sulfur ylide derived from diazoquinones and allyl/propargyl sulfides
Zhou, Cong-Ying,Yan, Sijia,Rao, Junxin
supporting information, p. 9091 - 9096 (2020/12/02)
Here, we describe three types of rearrangement reactions of sulfur ylide derived from diazoquinones and allyl/ propargyl sulfides. With Rh2(esp)2 as the catalyst, diazoquinones react with allyl/propargyl sulfides to form a sulfur ylide, which undergoes a chemoselective tautomerization/[2,3]-sigmatropic rearrangement reaction, a Doyle?Kirmse rearrangement/Cope rearrangement cascade reaction, or a Doyle?Kirmse rearrangement/elimination reaction, depending on the substituent of the sulfides. The protocol provides alkenyl and allenyl sulfides and multisubstituted phenols with moderate and high yields.
Cp?Rh(iii) and Cp?Ir(iii)-catalysed redox-neutral C-H arylation with quinone diazides: quick and facile synthesis of arylated phenols
Zhang, Shang-Shi,Jiang, Chun-Yong,Wu, Jia-Qiang,Liu, Xu-Ge,Li, Qingjiang,Huang, Zhi-Shu,Li, Ding,Wang, Honggen
supporting information, p. 10240 - 10243 (2015/06/22)
Cp?Rh(iii)- and Cp?Ir(iii)-catalysed direct C-H arylation with quinone diazides as efficient coupling partners is disclosed. This redox-neutral protocol offers a facile, operationally simple and environmentally benign access to arylated phenols. The reaction represents the first example of Cp?Ir(iii)-catalysed C-H direct arylation reaction.
An efficient procedure for the synthesis of crystalline aryldiazonium trifluoroacetates - Synthetic applications
Colas, Christophe,Goeldner, Maurice
, p. 1357 - 1366 (2007/10/03)
We have developed a very mild procedure for the synthesis of crystalline aryldiazonium trifluoroacetate salts in high yields under anhydrous conditions. Over thirty mono- or polyfunctional aniline derivatives have been diazotized by this method, including water- and acid-sensitive substrates. The o- and p-hydroxyaryldiazonium salts, derived from the corresponding anilines, could be deprotonated by treatment with K2CO3 to yield pure diazoquinones. NMR and UV/Vis spectra have been recorded for all the synthesized salts; the data are in good agreement with the rather limited published data and constitute a first extensive report of 13C-NMR chemical shifts in diazonium salts. An excellent linear relationship emerged between Brown's substituent constants S+(p) and the 13C(ipso) chemical shifts. The diazonium salts obtained proved to be much more soluble in organic solvents than their tetrafluoroborate counterparts. They were tested in Pd-mediated coupling reactions of various carbon-carbon double bonds, and were found to give good yields within short reaction times under very mild conditions. We believe that diazonium trifluoroacetates represent a very attractive alternative to diazonium tetrafluoroborates.
Preparation of aromatic fluorides: Facile photo-induced fluorinative decomposition of arenediazonium salts and their related compounds using pyridine-nHF
Sawaguchi, Masanori,Fukuhara, Tsuyoshi,Yoneda, Norihiko
, p. 127 - 133 (2007/10/03)
By employing pyridine-nHF solution, the photo-induced fluorinative decomposition of arenediazonium salts (ArN2BF4) (fluoro-dediazoniation) and the related compounds, such as quinonediazides and triazenes, has been successfully carried out to produce the corresponding aromatic fluorides (ArF) in good yields. The rate in the fluoro-dediazoniation of para-substituted ArN2BF4 in pyridine-nHF solution did not obey the classical Hammett equation but conformed well to Taft's treatment [dual substituent parameter relationships (DSP)]. In the thermal fluoro-dediazoniation of ArN2BF4 the rate of reaction was significantly influenced by the substituents in the substrates. On the contrary, only a slight effect by the substituents was observed on the rate of the photo-induced fluoro-dediazoniation of ArN2BF4.
Quinone-type methanofullerene acceptors: Precursors for organic metals
Ohno, Toshinobu,Martín, Nazario,Knight, Brian,Wudl, Fred,Suzuki, Toshiyasu,Yu, Huinan
, p. 1306 - 1307 (2007/10/03)
We report details on the synthesis and electrochemistry of quinone-type methanofullerene derivatives in which, depending upon the substitution pattern on the cyclohexanedienone moiety, the reduction potential can be tuned, leading to novel fullerene deriv
Pulsed Ultraviolet Laser Photolysis of Substituted Phenyl Diazosulphonates at 248 nm
Nomayo, M.,Wokaun, A.
, p. 1495 - 1503 (2007/10/02)
The photochemical decomposition of aqueous phenyl diazosulphonate solutions by KrF excimer laser pulses at 248 nm is investigated.The present study complements earlier investigations (Franzke et al. 1991, 1992) of the photochemistry of this class of compounds induced by irradiation at 308 nm (XeCl excimer laser), and in the 370-390 nm wavelength range (dye laser pulses).From the comparison, conclusions with regard to the wavelength dependent photolysis pathway are drawn.Phenyl diazosulphonates carrying methoxy- or ester-type substituents at the aromatic ring are observed to decompose in a two-step-reaction in aqueous solution: Photolysis proceeds via the phenyl diazonium ion as an intermediate, to yield the corresponding phenol as product.In contrast, the photolysis of 3-vinyl-phenyl diazosulphonate in aqueous solution at 248 nm results in a complex reaction involving via more than one intermediate.UV spectra recorded during photolysis show that products characterized by an absorption maximum at 272 nm are formed; these spectra are identical with those of final products from 308 nm photolysis, which are identified as 3-hydroxyethyl-phenols. - The photolysis pathway of 4-hydroxy-phenyl-diazosulphonate is found to proceed via the diazoquinone, instead of a diazonium ion.As a consequence of the high energy of 248 nm photons, the mentioned substituted phenols are not the final products of the photochemical reaction.These molecules are further decomposed by absorbing 248 nm photons; the quantum efficiency of these secondary photochemical reactions is lower by one to two orders of magnitude, as compared to the primary photolysis of the parent compounds. - Keywords: Light, Absorption / Materials Properties, Diazo Sulphonates / Photochemistry / Radicals / Spectroscopy, Ultraviolet
REACTION OF p-NITROBENZENEDIAZONIUM FLUOROBORATE WITH SODIUM p-NITROBENZENEDIAZOATE IN WATER
Kuplet-skaya, N. B.,Kazitsyna, L. A.
, p. 1114 - 1117 (2007/10/02)
During the reaction of p-nitrobenzenediazonium fluoroborate with sodium p-nitrobenzenediazoate in water nucleophilic substitution of the nitro group in the diazonium ion occurs.The main reaction product is p-diazophenol.
REACTION OF p-NITROBENZENEDIAZONIUM FLUOROBORATE WITH SODIUM p-NITROBENZENEDIAZOATE IN ACETONITRILE AND DIMETHYL SULFOXIDE
Kuplet-skaya, N. B.,Baranova, T. A.,Tikhonova, T. N.,Sychev, S. N.,Kazitsyna, L. A.
, p. 483 - 486 (2007/10/02)
The main products from the reaction of p-nitrobenzenediazonium fluoroborate with sodium p-nitrobenzenediazoate in acetonitrile are nitrobenzene and p-nitrophenol, which are formed as a result of attack by the diazoate at the diazonium group of the diazoni
Reactivity of Carbenes and Related Compounds towards Molecular Nitrogen
Grieve, Duncan M. A.,Lewis, Graham E.,Ravenscroft, Michael D.,Skrabal, Peter,Sonoda, Takaaki,et al.
, p. 1427 - 1443 (2007/10/02)
The thermal N2 exchange of a number of 15N-labelled diazo compounds was studied in solution.The compounds involved were 3-diazo-1-methylindolin-2-one (1), 9-diazafluorene (2), 5-diazo-1,3-cyclopentadiene-1,2,3,4-tetracarbonitrile (3), 2-diazo-2H-imidazole-4,5-dicarbonitrile (4), 4-diazocyclohexa-2,5-dienone (5), and the conjugate acids of 4 and 5, namely 4,5-dicyano-1H-imidazole-2-diazonium ion (6) and 4-hydroxybenzenediazonium ion (7).Only 1, 4, 6, and 7 exchange their diazo group with 'external' molecular N2.The results are explained on the hypothesis that only organic species which have an empty ? orbital and which are effective in ? electron back-donation are able to react with N2.Thus, reaction with carbenes is likely to occur only if the carbene is in the 1A2 singlet state and if its electrophilicity is high.
