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  2. Mannich reaction - Wikipedia

    en.wikipedia.org/wiki/Mannich_reaction

    In organic chemistry, the Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl (C=O) functional group by formaldehyde (H−CHO) and a primary or secondary amine (−NH 2) or ammonia (NH 3). [1] The final product is a β-amino-carbonyl compound also known as a Mannich base.

  3. Ring expansion and contraction - Wikipedia

    en.wikipedia.org/wiki/Ring_expansion_and_contraction

    Examples include high impact applications of the Beckmann rearrangement (for introduction of nitrogen into codeine) [14] and the Baeyer-Villiger oxidation (introduction of oxygen to cage-annulated ethers) [15] in synthesis. Both occur with the expulsion of a leaving group as the alkyl group migrates onto the exocyclic heteroatom, which is ...

  4. Solution (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Solution_(chemistry)

    Making a saline water solution by dissolving table salt in water.The salt is the solute and the water the solvent. In chemistry, a solution is defined by IUPAC as "A liquid or solid phase containing more than one substance, when for convenience one (or more) substance, which is called the solvent, is treated differently from the other substances, which are called solutes.

  5. Covalent bond - Wikipedia

    en.wikipedia.org/wiki/Covalent_bond

    In organic chemistry, when a molecule with a planar ring obeys Hückel's rule, where the number of π electrons fit the formula 4n + 2 (where n is an integer), it attains extra stability and symmetry. In benzene, the prototypical aromatic compound, there are 6 π bonding electrons (n = 1, 4n + 2 = 6).

  6. Physical fitness - Wikipedia

    en.wikipedia.org/wiki/Physical_fitness

    Physical fitness is achieved through exercise, among other factors.Photo shows Rich Froning Jr., four-time winner of "Fittest Man on Earth" title.. Physical fitness is a state of health and well-being and, more specifically, the ability to perform aspects of sports, occupations, and daily activities.

  7. Dying To Be Free - The Huffington Post

    projects.huffingtonpost.com/dying-to-be-free...

    Chemistry, not moral failing, accounts for the brain’s unwinding. In the laboratories that study drug addiction, researchers have found that the brain becomes conditioned by the repeated dopamine rush caused by heroin. “The brain is not designed to handle it,” said Dr. Ruben Baler, a scientist with the National Institute on Drug Abuse.

  8. 'Yellowstone' Season 5, Part 2: Here's when the final two ...

    www.aol.com/yellowstone-season-5-part-2...

    Here's when the final two episodes of Season 5, Part 2 of "Yellowstone" will come out and how you can watch. 'Yellowstone' recap: Kayce Dutton fights dirty and a new heartbreaking 'Yellowstone ...

  9. Substitution reaction - Wikipedia

    en.wikipedia.org/wiki/Substitution_reaction

    A good example of a substitution reaction is halogenation. When chlorine gas (Cl 2) is irradiated, some of the molecules are split into two chlorine radicals (Cl•), whose free electrons are strongly nucleophilic. One of them breaks a C–H covalent bond in CH 4 and grabs the hydrogen atom to form the electrically neutral HCl.