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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. Dynamic kinetic resolution in asymmetric synthesis - Wikipedia

    en.wikipedia.org/wiki/Dynamic_Kinetic_Resolution...

    Dynamic kinetic resolution in chemistry is a type of kinetic resolution where 100% of a racemic compound can be converted into an enantiopure compound. It is applied in asymmetric synthesis. Asymmetric synthesis has become a much explored field due to the challenge of creating a compound with a single 3D structure. [1]

  4. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    The artificial production of chemical substances already was a central goal for medieval alchemists. [3] Examples include the synthesis of ammonium chloride from organic substances as described in the works (c. 850–950) attributed to Jābir ibn Ḥayyān, [4] or the production of mineral acids such as sulfuric and nitric acids by later ...

  5. Asymmetric induction - Wikipedia

    en.wikipedia.org/wiki/Asymmetric_induction

    The Cram's rule of asymmetric induction named after Donald J. Cram states In certain non-catalytic reactions that diastereomer will predominate, which could be formed by the approach of the entering group from the least hindered side when the rotational conformation of the C-C bond is such that the double bond is flanked by the two least bulky groups attached to the adjacent asymmetric center. [3]

  6. Chemical thermodynamics - Wikipedia

    en.wikipedia.org/wiki/Chemical_thermodynamics

    The primary objective of chemical thermodynamics is the establishment of a criterion for determination of the feasibility or spontaneity of a given transformation. [3] In this manner, chemical thermodynamics is typically used to predict the energy exchanges that occur in the following processes: Chemical reactions; Phase changes; The formation ...

  7. Cascade reaction - Wikipedia

    en.wikipedia.org/wiki/Cascade_reaction

    Cascade reactions are often key steps in the efficient total synthesis of complex natural products. The key step in Heathcock's synthesis of dihydroprotodaphniphylline features a highly efficient cascade involving two aldehyde/amine condensations, a Prins-like cyclization, and a 1,5-hydride transfer to afford a pentacyclic structure from an acyclic starting material.

  8. Pericyclic reaction - Wikipedia

    en.wikipedia.org/wiki/Pericyclic_reaction

    Example of a pericycle reaction: the norcaradiene–cyclohexatriene rearrangement. In organic chemistry, a pericyclic reaction is the type of organic reaction wherein the transition state of the molecule has a cyclic geometry, the reaction progresses in a concerted fashion, and the bond orbitals involved in the reaction overlap in a continuous cycle at the transition state.

  9. Chemical energy - Wikipedia

    en.wikipedia.org/wiki/Chemical_energy

    Chemical energy is the energy of chemical substances that is released when the substances undergo a chemical reaction and transform into other substances. Some examples of storage media of chemical energy include batteries, [1] food, and gasoline (as well as oxygen gas, which is of high chemical energy due to its relatively weak double bond [2] and indispensable for chemical-energy release in ...