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  2. List of unsolved problems in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    Protein folding problem: Is it possible to predict the secondary, tertiary and quaternary structure of a polypeptide sequence based solely on the sequence and environmental information? Inverse protein-folding problem: Is it possible to design a polypeptide sequence which will adopt a given structure under certain environmental conditions?

  3. Retrosynthetic analysis - Wikipedia

    en.wikipedia.org/wiki/Retrosynthetic_analysis

    The synthesis of phenylacetic acid determined by retrosynthetic analysis is thus: PhCH 2 Br + NaCN → PhCH 2 CN + NaBr PhCH 2 CN + 2 H 2 O → PhCH 2 COOH + NH 3. In fact, phenylacetic acid has been synthesized from benzyl cyanide, [9] itself prepared by the analogous reaction of benzyl bromide with sodium cyanide. [10]

  4. Chemical synthesis - Wikipedia

    en.wikipedia.org/wiki/Chemical_synthesis

    This requires mixing the compounds in a reaction vessel, such as a chemical reactor or a simple round-bottom flask. Many reactions require some form of processing ("work-up") or purification procedure to isolate the final product. [1] The amount produced by chemical synthesis is known as the reaction yield.

  5. Fukuyama coupling - Wikipedia

    en.wikipedia.org/wiki/Fukuyama_coupling

    Although the Fukuyama cross-coupling reaction has been widely used in natural product synthesis, the reaction mechanism remains unclear.Various catalysts have been shown to promote reactivity, including Pd/C, Pd(OH) 2 /C, Pd(OAc) 2, PdCl 2, NiCl 2, Ni(acac) 2, etc. [2] The proposed catalytic cycle using Pd(OH) 2 /C (Pearlman’s catalyst) features the in situ generation of active Pd/C by ...

  6. Williamson ether synthesis - Wikipedia

    en.wikipedia.org/wiki/Williamson_ether_synthesis

    The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol . This reaction was developed by Alexander Williamson in 1850. [ 2 ] Typically it involves the reaction of an alkoxide ion with a primary alkyl halide via an S N 2 reaction .

  7. Hantzsch pyridine synthesis - Wikipedia

    en.wikipedia.org/wiki/Hantzsch_pyridine_synthesis

    [1] [2] The initial reaction product is a dihydropyridine which can be oxidized in a subsequent step to a pyridine. [3] The driving force for this second reaction step is aromatization. This reaction was reported in 1881 by Arthur Rudolf Hantzsch. A 1,4-dihydropyridine dicarboxylate is also called a 1,4-DHP compound or a Hantzsch ester.

  8. Pellizzari reaction - Wikipedia

    en.wikipedia.org/wiki/Pellizzari_reaction

    Liquid-phase synthesis of 3-alkylamino-4,5-disubstituted-1,2,4-triazoles by PEG support has given moderate yields with excellent purity. [4] In practice, the Pellizzari reaction requires high temperatures, long reaction times, and has an overall low yield. However, adding microwave irradiation shortens the reaction time and increases its yield. [5]

  9. Organic synthesis - Wikipedia

    en.wikipedia.org/wiki/Organic_synthesis

    Before beginning any organic synthesis, it is important to understand the chemical reactions, reagents, and conditions required in each step to guarantee successful product formation. When determining optimal reaction conditions for a given synthesis, the goal is to produce an adequate yield of pure product with as few steps as possible. [13]