Related Experiment Video

Updated: Jun 1, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
11:51

Facile Preparation of 4-Substituted Quinazoline Derivatives

Published on: February 15, 2016

1-(Benzothia-zol-2-yl)-3-(4-nitro-benzo-yl)thio-urea

Sohail Saeed, Naghmana Rashid, Rizwan Hussain

    Acta Crystallographica. Section E, Structure Reports Online
    |May 18, 2011
    PubMed

    More Related Videos

    Modification and Functionalization of the Guanidine Group by Tailor-made Precursors09:45

    Modification and Functionalization of the Guanidine Group by Tailor-made Precursors

    Published on: April 27, 2017

    Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives08:43

    Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

    Published on: January 19, 2016

    Related Concept Videos

    Electrophilic Aromatic Substitution: Nitration of Benzene01:20

    Electrophilic Aromatic Substitution: Nitration of Benzene

    The nitration of benzene is an example of an electrophilic aromatic substitution reaction. It involves the formation of a very powerful electrophile, the nitronium ion, which is linear in shape. The reaction occurs through the interaction of two strong acids, sulfuric and nitric acid.
    Diazonium Group Substitution: –OH and –H01:19

    Diazonium Group Substitution: –OH and –H

    Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
    Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN101:14

    Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1

    Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
    In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
    Nucleophilic Aromatic Substitution: Elimination–Addition01:11

    Nucleophilic Aromatic Substitution: Elimination–Addition

    Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is confirmed through isotopic...
    Preparation of Nitriles01:12

    Preparation of Nitriles

    One of the common methods to prepare nitriles is the dehydration of amides. This method requires strong dehydrating agents like phosphorous pentoxide or boiling acetic anhydride for converting amides to nitriles. Another reagent namely, thionyl chloride also accomplishes the dehydration of amides, where amide acts as a nucleophile. The first step of the mechanism involves the nucleophilic attack by the amide on the thionyl chloride to form an intermediate. In the next step, the electron pairs...
    1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism01:37

    1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism

    Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.