4733-50-0Relevant articles and documents
The synthesis of symmetrically octa-substituted phthalocyanines and their physical and photo-physical properties
Gao, Detao,Xu, Haitao,Van Tiantang,Peng, Bixian
, p. 1189 - 1196 (2001)
A series of symmetrically substituted phthalocyanines have been synthesized from 3,6-dialkoxy-phthalonitrile and the corresponding metal salts. All of these complexes are extremely soluble in chloroform. Their melting points vary greatly with their different substituents. Their structures are confirmed by elemental analysis, 1H NMR, UV-VIS.
Non-peripherally alkylamino-substituted phthalocyanines: Synthesis, spectral, photophysical and acid-base properties
Kociscakova, Lucia,Senipek, Merve Ipek,Zimcik, Petr,Novakova, Veronika
, p. 427 - 436 (2019)
Non-peripherally substituted metal-free and zinc phthalocyanines (Pcs) bearing four diethylamino groups and four Br atoms were prepared. Optimal conditions for synthesis of corresponding precursor (i.e. 3-bromo-6-(diethylamino)phthalonitrile) either by nucleophilic substitution or by Buchwald-Hartwig coupling were studied. Noteworthy, 3,6-bis(diethylamino)phthalonitrile was also formed, nevertheless only at low yield (typically below 1%) and all attempts for its cyclotetramerization failed. Q bands of prepared Pcs were strongly red shifted up to the near-IR region (769 and 800 nm in THF for zinc and metal-free Pc, respectively). Unusually large hypsochromic shifts of the Q bands, 130 and 80 nm for metal-free and zinc Pc, respectively, were observed upon treating these Pcs with trifluoroacetic acid, which was attributed to the protonation of non-peripheral amines. Treatment with sulfuric acid led to subsequent protonation on the azomethine nitrogens as well. Photophysical study revealed low fluorescence emission of both derivatives (φF 0.03, in THF) and efficient singlet oxygen production only for zinc Pc (φΔ = 0.77 in THF and 0.60 in DMF).
Method for preparing p-benzoquinone through catalytic oxidation of 1, 4-benzenediol
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Paragraph 0022, (2021/07/28)
The invention discloses a method for preparing p-benzoquinone through catalytic oxidation of 1, 4-benzenediol. The method comprises the following steps: carrying out centrifugal treatment on mother liquor for preparing 2, 3-dicyanohydroquinone; adding the centrifuged mother liquor and sodium hypochlorite into a micro-channel reactor; sequentially mixing and stirring the to-be-reacted liquid added into the microchannel reactor, and then crystallizing and filtering; and adding water into solid phase benzoquinone obtained after crystallization treatment for washing to obtain a p-benzoquinone product. According to the invention, the problem of waste of raw materials caused by conversion of the raw materials into 1, 4-benzenediol in the preparation process of 2, 3-dicyanohydroquinone at present is solved.
Pd-Catalyzed debenzylation and deallylation of ethers and esters with sodium hydride
Mao, Yujian,Liu, Ye,Hu, Yanwei,Wang, Liang,Zhang, Shilei,Wang, Wei
, p. 3016 - 3020 (2018/04/14)
Herein we demonstrate simply that the addition of Pd(OAc)2 as a promotor switches the reactivity of a commonly used base NaH to a nucleophilic reductant. The reactivity is engineered into a palladium-catalyzed reductive debenzylation and deallylation of aryl ethers and esters. This operationally simple, mild protocol displays a broad substrate scope and a broad spectrum of functional group tolerance (>50 examples) and high chemoselectivity toward aryl ethers over aliphatic structures. Moreover, the dual reactivity of NaH as a base and a reductant is demonstrated in efficient synthetic elaboration.
Synthesis of 1,3,5,8-Tetrahydroxy-2-methylanthraquinone and Its 3-O-β-D-Glucopyranoside
Singh, Janhavi,Singh, J.
, p. 969 - 970 (2007/10/02)
1,3,5,8-Tetrahydroxy-2-methylanthraquinone (I) and its 3-O-β-D-glucopyranoside (II) have been synthesised.Condensation of 3,6-dihydroxyphthalic anhydride (IV) with 2,6-dihydroxytoluene (V) in the presence of anhyd.AlCl3 followed by cyclisation of the resultant o-benzoylbenzoic acid derivative (III) with sulphuric acid containing boric acid gives the anthraquinone I.Treatment of I with acetobromoglucose in alkaline medium followed by deacetylation furnishes the glycoside (II).
THE HYDROCYANATION OF FREE AND POLYMER-BOUND BENZOQUINONE
Perry, Gregory J.,Sutherland, Maurice D.
, p. 1471 - 1476 (2007/10/02)
The polimer-bound quinone 2 has been prepared and used in column form with organic solvents for the convenient preparation of other quinones.In contrast to the solution reaction hydrocyanation of this quinone by the Thiele-Meisenheimer reaction did not yield a useful proportion of polymer-bound dicyanohydroquinone but instead gave a mixture of products including much monocyanohydroquinone.Helferich and Bodenbender's 2,3-dicyanocyclohexan-1,4-dione is in fact wholly the di-enol and is a likely intermediate in the hydrocyanation of benzoquinone, being oxidised by the latter to 2,3-dicyanocyclohex-2-ene-1,4-dione which tautomerises to the observed product, 2,3-dicyanohydroquinone.A lower accessibility to polymer-bound reactants as compared with those in solution is implied by these results.
