enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. SMILES arbitrary target specification - Wikipedia

    en.wikipedia.org/wiki/Smiles_arbitrary_target...

    Four logical operators allow atom and bond descriptors to be combined. The 'and' operator ; can be used to define a protonated primary amine as [N;H3;+][C;X4]. The 'or' operator , has a higher priority so [c,n;H] defines (aromatic carbon or aromatic nitrogen) with implicit hydrogen.

  3. Amine - Wikipedia

    en.wikipedia.org/wiki/Amine

    Amine. In chemistry, amines (/ ə ˈ m iː n, ˈ æ m iː n /, [1] [2] UK also / ˈ eɪ m iː n / [3]) are compounds and functional groups that contain a basic nitrogen atom with a lone pair.Formally, amines are derivatives of ammonia (NH 3 (in which the bond angle between the nitrogen and hydrogen is 170°), wherein one or more hydrogen atoms have been replaced by a substituent such as an ...

  4. Mannich reaction - Wikipedia

    en.wikipedia.org/wiki/Mannich_reaction

    Reactions between aldimines and α-methylene carbonyls are also considered Mannich reactions because these imines form between amines and aldehydes. The reaction is named after Carl Mannich. [2] [3] Scheme 1 – Ammonia or an amine reacts with formaldehyde and an alpha acidic proton of a carbonyl compound to a beta amino carbonyl compound.

  5. 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?

  6. Baylis–Hillman reaction - Wikipedia

    en.wikipedia.org/wiki/Baylis–Hillman_reaction

    In organic chemistry, the Baylis–Hillman, Morita–Baylis–Hillman, or MBH reaction is a carbon-carbon bond-forming reaction between an activated alkene and a carbon electrophile in the presence of a nucleophilic catalyst, such as a tertiary amine or phosphine.

  7. Hydroamination - Wikipedia

    en.wikipedia.org/wiki/Hydroamination

    In organic chemistry, hydroamination is the addition of an N−H bond of an amine across a carbon-carbon multiple bond of an alkene, alkyne, diene, or allene. [1] In the ideal case, hydroamination is atom economical and green. [2] Amines are common in fine-chemical, pharmaceutical, and agricultural industries.

  8. Buchwald–Hartwig amination - Wikipedia

    en.wikipedia.org/wiki/Buchwald–Hartwig_amination

    In organic chemistry, the Buchwald–Hartwig amination is a chemical reaction for the synthesis of carbon–nitrogen bonds via the palladium-catalyzed coupling reactions of amines with aryl halides. [1]

  9. Demjanov rearrangement - Wikipedia

    en.wikipedia.org/wiki/Demjanov_rearrangement

    The reaction process begins with diazotization of the amine by nitrous acid. The diazonium group is a good leaving group, forming nitrogen gas when displaced from the organic structure. This displacement can occur via a rearrangement (path A), in which one of the sigma bonds adjacent to the diazo group migrates. This migration results in an ...