enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Chemical synthesis - Wikipedia

    en.wikipedia.org/wiki/Chemical_synthesis

    For example, the synthesis of paracetamol typically requires three separate reactions. Divergent synthesis starts with a common intermediate, which branches into multiple final products through distinct reaction pathways. Convergent synthesis synthesis involves the combination of multiple intermediates synthesized independently to create a ...

  3. Combinatorial chemistry - Wikipedia

    en.wikipedia.org/wiki/Combinatorial_chemistry

    In the synthesis of a sublibrary the support is not divided and only one amino acid is coupled to the whole sample. As a result, one position is really occupied by the same amino acid in all components. For example, in the B2 sublibrary position 2 is occupied by the "yellow" amino acid in all the nine components.

  4. McMurry reaction - Wikipedia

    en.wikipedia.org/wiki/McMurry_reaction

    In another example, the Nicolaou's total synthesis of Taxol uses this reaction, although coupling stops with the formation of a cis-diol, rather than an olefin. Optimized procedures employ the dimethoxyethane complex of TiCl 3 in combination with the Zn(Cu). The first porphyrin isomer, porphycene, was synthesised by McMurry coupling. [8]

  5. Click chemistry - Wikipedia

    en.wikipedia.org/wiki/Click_chemistry

    This reaction has been used successfully to probe for azides in living systems, even though the reaction rate is somewhat slower than that of the CuAAC. Moreover, because the synthesis of cyclooctynes often gives low yield, probe development for this reaction has not been as rapid as for other reactions.

  6. Pauson–Khand reaction - Wikipedia

    en.wikipedia.org/wiki/Pauson–Khand_reaction

    The Pauson–Khand (PK) reaction is a chemical reaction, described as a cycloaddition.In it, an alkyne, an alkene, and carbon monoxide combine into a α,β-cyclopentenone in the presence of a metal-carbonyl catalyst [1] [2] Ihsan Ullah Khand (1935–1980) discovered the reaction around 1970, while working as a postdoctoral associate with Peter Ludwig Pauson (1925–2013) at the University of ...

  7. Simmons–Smith reaction - Wikipedia

    en.wikipedia.org/wiki/Simmons–Smith_reaction

    The reaction can also be quenched with pyridine, which will scavenge ZnI 2 and excess reagents. [24] Methylation of heteroatoms is also observed in the Simmons–Smith reaction due to the electrophilicity of the zinc carbenoids. For example, the use of excess reagent for long reaction times almost always leads to the methylation of alcohols. [25]

  8. Henry reaction - Wikipedia

    en.wikipedia.org/wiki/Henry_reaction

    The first example of an enantioselective nitroaldol reaction was reported in 1992 using Shibasaki catalysts. [11] One of the most frequently employed methods for inducing enantio- or diastereoselectivity in the Henry reaction is the use of chiral metal catalysts, in which the nitro group and carbonyl oxygen coordinate to a metal that is bound ...

  9. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    One example of a synthesis reaction is the combination of iron and sulfur to form iron(II) sulfide: + Another example is simple hydrogen gas combined with simple oxygen gas to produce a more complex substance, such as water.