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  2. Methoxy group - Wikipedia

    en.wikipedia.org/wiki/Methoxy_group

    In nature, methoxy groups are found on nucleosides that have been subjected to 2′-O-methylation, for example in variations of the 5′-cap structure known as cap-1 and cap-2. They are also common substituents in O -methylated flavonoids , whose formation is catalyzed by O-methyltransferases that act on phenols , such as catechol- O -methyl ...

  3. Oxonium ion - Wikipedia

    en.wikipedia.org/wiki/Oxonium_ion

    Extreme acidity, heat, and dehydrating conditions are usually required. Other hydrocarbon oxonium ions are formed by protonation or alkylation of alcohols or ethers (R−C− + −R 1 R 2). Secondary oxonium ions have the formula R 2 OH +, an example being protonated ethers. Tertiary oxonium ions have the formula R 3 O +, an example being ...

  4. List of common physics notations - Wikipedia

    en.wikipedia.org/wiki/List_of_common_physics...

    cubic meter (m 3) electric field: newton per coulomb (N⋅C −1), or equivalently, volt per meter (V⋅m1) energy: joule (J) Young's modulus: pascal (Pa) or newton per square meter (N/m 2) eccentricity: unitless Euler's number (2.71828, base of the natural logarithm) unitless electron: unitless elementary charge: coulomb (C)

  5. Inductive effect - Wikipedia

    en.wikipedia.org/wiki/Inductive_effect

    In Organic chemistry, the inductive effect in a molecule is a local change in the electron density due to electron-withdrawing or electron-donating groups elsewhere in the molecule, resulting in a permanent dipole in a bond. [1] It is present in a σ (sigma) bond, unlike the electromeric effect which is present in a π (pi) bond.

  6. ISO 31-8 - Wikipedia

    en.wikipedia.org/wiki/ISO_31-8

    In the tables of quantities and their units, the ISO 31-8 standard shows symbols for substances as subscripts (e.g., c B, w B, p B). It also notes that it is generally advisable to put symbols for substances and their states in parentheses on the same line, as in c (H 2 SO 4 ).

  7. Trimethyl phosphite - Wikipedia

    en.wikipedia.org/wiki/Trimethyl_phosphite

    P(OCH 3) 3 → CH 3 P(O)(OCH 3) 2. As a ligand, trimethyl phosphite has a smaller cone angle and better acceptor properties relative to trimethylphosphine. A representative derivative is the colorless tetrahedral complex Ni(P(OMe) 3) 4 (m.p. 108 °C). [4] The tridentate ligand called the Kläui ligand is derived from trimethyl phosphite. The ...

  8. Mesomeric effect - Wikipedia

    en.wikipedia.org/wiki/Mesomeric_effect

    The +M effect, also known as the positive mesomeric effect, occurs when the substituent is an electron donating group. The group must have one of two things: a lone pair of electrons, or a negative charge. In the +M effect, the pi electrons are transferred from the group towards the conjugate system, increasing the density of the system.

  9. Period 3 element - Wikipedia

    en.wikipedia.org/wiki/Period_3_element

    A period 3 element is one of the chemical elements in the third row (or period) of the periodic table of the chemical elements.The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases: a new row is begun when chemical behavior begins to repeat, meaning that elements with similar behavior fall into ...