24324-17-2Relevant articles and documents
Formation and verification of the structure of the 1-fluorenylmethyl chloroformative derivative of sulfamethazine
Liang,Zhang,Baker,Cross
, p. 86 - 92 (1996)
Sulfamethazine (SMZ) is derivatized with 1-fluorenylmethyl chloroformate (FMOC) to form the fluorescent adduct SMZ-FMOC. Conditions for formation are optimized with respect to pH, reagent concentration, and reagent ratio. Reagent and product profiles (including the hydrolysis byproduct FMOC-OH) versus time are followed by reversed phase HPLC with UV absorbance detection. FMOC-SMZ has been crystallized, its composition confirmed by microanalysis, and its structure corroborated by IR and NMR spectroscopy. From 10 down to 1 ppm, there is clear gentle curvature in the fluorescence intensity of SMZ-FMOC. The linear response range extends from above 100 ppb down to about 100 ppt, and an increase in sensitivity for the fluorescent detection of FMOC-SMZ (over the usual UV absorbance detection of SMZ) is calculated to be better than 3 orders of magnitude.
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Brown,Bluestein
, (1943)
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Method for high-selectivity synthesis of 9-fluorenylcarbinol
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Paragraph 0025-0080, (2021/06/06)
The invention discloses a method for high-selectivity synthesis of 9-fluorenylcarbinol. The method comprises the following steps: heating and dissolving fluorene in a DMSO solvent system at 50-55 DEG C in the presence of a sodium ethoxide ethanol solution alkali catalyst, adding an acylation reagent ethyl formate, carrying out acylation reaction at the same temperature to prepare 9-fluorenylformaldehyde, adding a soluble metal inorganic salt auxiliary agent, then using NaBH4 for a reduction reaction, adjusting the pH value of reaction liquid to be neutral, and separating out 9-fluorene methanol solid sediment. According to the method disclosed by the invention, fluorene is completely converted by utilizing a section of temperature, the 9-fluorene methanol can be obtained through high-selectivity reduction without solvent conversion by adding the soluble metal inorganic salt auxiliary agent, and the yield of the 9-fluorene methanol is improved on the premise of shortening the reaction time.
KMnO4-catalyzed chemoselective deprotection of acetate and controllable deacetylation-oxidation in one pot
Gurawa, Aakanksha,Kumar, Manoj,Rao, Dodla S.,Kashyap, Sudhir
supporting information, p. 16702 - 16707 (2020/10/27)
A novel and efficient protocol for chemoselective deacetylation under ambient conditions was developed using catalytic KMnO4. The stoichiometric use of KMnO4 highlighted the dual role of a heterogeneous oxidant enabling direct access to aromatic aldehydes in one-pot sequential deacetylation-oxidation. The reaction employed an alternative solvent system and allowed the clean transformation of benzyl acetate to sensitive aldehyde in a single step while preventing over-oxidation to acids. Use of inexpensive and readily accessible KMnO4 as an environmentally benign reagent and the ease of the reaction operation were particularly attractive, and enabled the controlled oxidation and facile cleavage of acetate in a preceding step. This journal is
Additive-free cobalt-catalysed hydrogenation of carbonates to methanol and alcohols
Ferretti, Francesco,Scharnagl, Florian Korbinian,Dall'Anese, Anna,Jackstell, Ralf,Dastgir, Sarim,Beller, Matthias
, p. 3548 - 3553 (2019/07/10)
Reduction of various organic carbonates to methanol and alcohols can be achieved in the presence of a molecularly-defined homogeneous cobalt catalyst. Specifically, the use of Co(BF4)2 in combination with either commercial or tailor-made tridentate phosphine ligands allows for additive-free hydrogenations of carbonates. Optimal results are obtained at relatively mild conditions (120 °C, 50 bar hydrogen pressure) in the presence of xylyl-Triphos L4.